docs: record the aim-capture blind spot - aim_fire only logs shots that passed setFire

j178 flagged it and it is real: the capture cannot show WHY a shot did not happen (gun still hot, turret not aligned). A missing aim_fire record is ambiguous, not a refusal. Docs only, no code change. Adds the TR_CAPTURE_AIM row + a 'Known limitations' note to docs/env_reference.md section 8, and a two-line pointer next to the knob in .env.example.
j177: aim capture - log what the model BELIEVED, not what it did
2026-09-27 18:53:59 +02:00 · 2026-09-27 18:44:24 +02:00 · 2026-09-27 15:05:14 +02:00
9 changed files with 654 additions and 1 deletions
@@ -153,6 +153,9 @@
 #     TR_SURF_LOG             one line per wave-surfing decision
 #     TR_FIRE_DIAG            per-reading fire-detection tick/raw/correction
 #     TR_RECORD_WORLDSTATE    dump every observed world state to JSONL
+#     TR_CAPTURE_AIM          aim_scan/aim_fire records (gun id + bot belief).
+#                             KNOWN LIMIT: only shots that PASSED setFire are
+#                             recorded, so a gap is ambiguous - see docs/env_reference.md
 #     TR_RADAR_SCANLOG        log every radar scan tick
 #     TR_RADAR_FORCE_SPIN     force the old full-360 spin radar
 #     TR_TRACKER_PROBE        dump the enemy-tracker internals
@@ -737,6 +740,24 @@ GUN_STATS_PATH=/tmp/gun_stats.jsonl   # where the per-round gun stats are writte
 GUN_SHOTLOG_PATH=/tmp/shot_log.jsonl  # where the per-shot log is written

 # ── measurement helpers (leave off unless you are measuring) ─────────────────
+# WHAT: aim capture. Adds TWO record kinds to the TR_RECORD_WORLDSTATE file:
+#   aim_scan — one per radar scan: the raw reading, our own state, the gun
+#     that fired, the PREVIOUS tracker belief, and the scan parity
+#     (age = tick - previous lastSeenTick);
+#   aim_fire — one per real shot: gun, power, the aim angle, the turret error,
+#     gun heat, the predicted intercept/TOF, and the exact WorldState the
+#     predictor consumed (with the tick it came from). It also adds the `gun`
+#     id to the per-tick world-state rows.
+# VALUES: presence-only, like the other keys in this block. Unset = off.
+# STATUS: default-off, diagnostic only, never live-tested. j176 could not
+#   attribute the 11.9 deg aim error because the corpus had no gun id and no
+#   bot-side belief; this knob makes both a lookup instead of an inverse
+#   problem. No aim model changed with it.
+# GOTCHA: it only writes when TR_RECORD_WORLDSTATE is on as well, and it makes
+#   the capture file bigger, not different: the extra lines are annotations and
+#   the offline replay skips them.
+# TRY:    TR_RECORD_WORLDSTATE=1 TR_CAPTURE_AIM=1 ./out/ModularBot
+#TR_CAPTURE_AIM=1      # PRESENCE-only: aim_scan / aim_fire records (needs TR_RECORD_WORLDSTATE)
 #TR_RECORD_WORLDSTATE=1 # PRESENCE-only: dump every observed world state
 #TR_RADAR_SCANLOG=1     # PRESENCE-only: log every radar scan tick
 #TR_TRACKER_PROBE=1     # PRESENCE-only: dump the enemy-tracker's internal state
@@ -44,6 +44,7 @@ import movement_harness/bullet_shadows
 import targeting/enemy_tracker
 import targeting/target_selector
 import env_report
+import aim_capture
 import vbullet_draw
 import geo_overlay

@@ -69,6 +70,13 @@ const ShotLog = true
 ## can enable recording for just the battle it spawns by exporting the env var.
 let RecordWorldState* = existsEnv("TR_RECORD_WORLDSTATE")
 const WorldStateRecordPath = "/tmp/worldstate_record.jsonl"
+## j177 aim capture: with TR_CAPTURE_AIM set, append two extra record kinds to
+## the SAME world-state file — `aim_scan` (one per radar scan: the raw reading,
+## our own state, the GUN, the previous belief and the scan parity) and
+## `aim_fire` (one per firing decision: the gun, the power, the aim angle, the
+## turret error, and the exact WorldState the predictor consumed). Off by
+## default, so a normal run writes byte-for-byte what it wrote before.
+let CaptureAim* = existsEnv("TR_CAPTURE_AIM")
 ## Radar measurement switches (all RUNTIME, read once at process start):
 ##   TR_RADAR_FORCE_SPIN=1  force the melee radar to the old stateless full
 ##                          spin (always 45 deg/tick). This reproduces the
@@ -477,6 +485,9 @@ proc recordWorldState(bot: ModularBot, ws: WorldState) =
      "eid": tid,
    }
    if lst >= 0: row["lst"] = %lst
+    # j177: the gun in force when this state was built. Absent before j177,
+    # which made a per-gun decomposition of the aim error impossible.
+    if CaptureAim: row["gun"] = %bot.currentGun
    try:
      let f = open(WorldStateRecordPath, fmAppend)
      f.writeLine($row)
@@ -616,6 +627,23 @@ proc recordRadarStats(bot: ModularBot) =
    inc bot.arcWidthHist[min(11, int(width / 30.0))]

 method onScannedBot*(bot: ModularBot, e: ScannedBotEvent) =
+  # j177 aim capture: the belief we are about to REPLACE, and the fire site's
+  # state, recorded BEFORE the update. Written first so the record is the
+  # pre-update belief by construction, not by argument.
+  if CaptureAim:
+    var rec = AimScan(tick: bot.tick, eid: e.scannedBotId,
+                      ex: e.x, ey: e.y, eh: e.direction, es: e.speed, ee: e.energy,
+                      sx: getX(), sy: getY(), sh: getDirection(), ss: getSpeed(),
+                      gun: bot.currentGun,
+                      rlock: bot.radarMode == 0, rdir: getRadarDirection(),
+                      bx: 0.0, by: 0.0, blst: -1)
+    if bot.enemyTracker.enemies.contains(e.scannedBotId):
+      let prev = bot.enemyTracker.enemies[e.scannedBotId]
+      rec.bx = prev.x; rec.by = prev.y; rec.bh = prev.heading
+      rec.bs = prev.speed; rec.blst = prev.lastSeenTick
+    rec.lbear = bearing(rec.bx, rec.by, rec.sx, rec.sy)
+    rec.boff = (bearing(rec.ex, rec.ey, rec.sx, rec.sy) - rec.rdir) mod 360.0
+    appendLine(WorldStateRecordPath, scanRow(rec))
  bot.enemyTracker.update(e.scannedBotId, e.x, e.y, e.direction, e.speed, e.energy, bot.tick)
  bot.hasContact = true
  if RadarScanLog and bot.radarMeleeActive:
@@ -1467,6 +1495,22 @@ method run*(bot: ModularBot) =
        # Enqueue the selected gun so onBulletFired can stamp the server's bulletId.
        # getEnergy() > power mirrors the server's "bot.energy <= firepower" reject.
        if not floorBlocks and setFire(power) and getEnergy() > power:
+          # j177 aim capture: one `aim_fire` line per REAL shot, with the gun
+          # that fired and the exact WorldState the predictor consumed. This
+          # is the only place where `lst` is knowable, so it is the only place
+          # the scan parity of a firing decision can be recorded.
+          if CaptureAim:
+            let bspd = bulletSpeed(power)
+            appendLine(WorldStateRecordPath, fireRow(AimFire(
+              tick: bot.tick, eid: tid, gun: selectedGun, power: power,
+              aim: aimTarget, turret: gunDir, terr: normDelta, heat: gunHeat,
+              ax: pred.x, ay: pred.y, tof: (if bspd > 0: distPx / bspd else: 0.0),
+              ex: bot.lastState.enemyX, ey: bot.lastState.enemyY,
+              eh: bot.lastState.enemyHeading, es: bot.lastState.enemySpeed,
+              ee: bot.lastState.enemyEnergy,
+              sx: bot.lastState.selfX, sy: bot.lastState.selfY,
+              lst: (if tid >= 0 and bot.enemyTracker.enemies.contains(tid):
+                      bot.enemyTracker.enemies[tid].lastSeenTick else: -1))))
          bot.pendingFires.add(PendingShot(
            gunId:    selectedGun,
            angleErr: abs(normDelta),
@@ -1558,6 +1602,7 @@ when isMainModule:
    vBulletDebugGun:  getEnv(VBulletDebugGunEnv, ""),
    vBulletDebugMax:  VBulletDebugMax,
    recordWorldState: RecordWorldState,
+    captureAim: CaptureAim,
    geoDebug:         GeoDebugOn,
    debugDraw:        DebugDrawOn,
    radarForceSpin:   RadarForceSpin,
@@ -0,0 +1,129 @@
+## j177 aim capture — the two records that make the aim error ATTRIBUTABLE.
+##
+## j176 could not answer "why is the aim 11.9 deg off at 450+ px" because the
+## corpus has neither the bot's own belief (staleness was an INVERSE problem,
+## unidentifiable) nor the gun id (a good gun's contribution was
+## indistinguishable from a bad one's). Both are cheap to log and impossible
+## to recover later. This module builds the two JSON records; ModularBot.nim
+## calls it and the lines go into the EXISTING world-state capture
+## (`TR_RECORD_WORLDSTATE` file), so the offline tooling sees one stream.
+##
+## It is deliberately PURE (no bot API, no env reads): the bot passes plain
+## floats, the offline guard test passes the recorded fixture, and both go
+## through the SAME row builders — so a field that the test proves present is
+## a field the live bot writes.
+##
+## Key convention: `e*` = the enemy, `s*` = us, `b*` = the enemy's PREVIOUS
+## belief in the tracker (before this scan's update), `lst` = the tick that
+## state came from. `age = tick - blst` is the scan PARITY, recorded rather
+## than inferred.
+
+import std/[json, os, math]
+
+const
+  ScanRecordKey* = "aim_scan"   ## wrapper key, sibling of "meta"/"end"
+  FireRecordKey* = "aim_fire"
+
+type
+  AimScan* = object
+    ## One `onScannedBot` event, as the bot saw it BEFORE the update.
+    tick*:       int
+    eid*:        int
+    ex*, ey*:    float   ## raw scanned values
+    eh*, es*:    float   ## scanned heading (= direction) and speed
+    ee*:         float
+    sx*, sy*:    float   ## our state at the scan (the FIRE SITE)
+    sh*, ss*:    float
+    gun*:        int     ## bot.currentGun — the gun that fired, not the rack slot
+    bx*, by*:    float   ## previous belief, BEFORE this scan's update
+    bh*, bs*:    float
+    blst*:       int     ## previous lastSeenTick; -1 = never scanned before
+    rlock*:      bool    ## radar lock engaged (false = the melee radar)
+    rdir*:       float   ## 36 deg scan window centre (radar heading)
+    lbear*:      float   ## bearing the lock is chasing (believed target)
+    boff*:       float   ## scanned bearing - rdir: where in the window it landed
+
+  AimFire* = object
+    ## One firing decision, as the model computed it.
+    tick*:       int
+    eid*:        int
+    gun*:        int     ## bot.currentGun = the gun that fired
+    power*:      float
+    aim*:        float   ## the raw angle handed to setFire/turret
+    turret*:     float   ## getGunDirection() at the command
+    terr*:       float   ## signed turret error (aim - turret)
+    heat*:       float   ## getGunHeat() BEFORE firing
+    ax*, ay*:    float   ## the intercept the gun predicted
+    tof*:        float   ## implied time of flight, ticks
+    ex*, ey*:    float   ## the WorldState the predictor CONSUMED
+    eh*, es*:    float
+    ee*:         float
+    sx*, sy*:    float
+    lst*:        int     ## which tick that enemy state came from (scan parity)
+
+proc bearing*(x, y, fx, fy: float): float =
+  arctan2(y - fy, x - fx).radToDeg
+
+proc scanRow*(s: AimScan): JsonNode =
+  ## The `aim_scan` line. Every field is unconditional: a capture that
+  ## silently omits a field is worse than no capture.
+  result = newJObject()
+  result[ScanRecordKey] = newJObject()
+  let b = result[ScanRecordKey]
+  b["tick"] = %s.tick
+  b["eid"] = %s.eid
+  b["ex"] = %s.ex
+  b["ey"] = %s.ey
+  b["eh"] = %s.eh
+  b["es"] = %s.es
+  b["ee"] = %s.ee
+  b["sx"] = %s.sx
+  b["sy"] = %s.sy
+  b["sh"] = %s.sh
+  b["ss"] = %s.ss
+  b["gun"] = %s.gun
+  b["bx"] = %s.bx
+  b["by"] = %s.by
+  b["bh"] = %s.bh
+  b["bs"] = %s.bs
+  b["blst"] = %s.blst
+  b["age"] = %(if s.blst >= 0: s.tick - s.blst else: -1)
+  b["rlock"] = %s.rlock
+  b["rdir"] = %s.rdir
+  b["lbear"] = %s.lbear
+  b["boff"] = %s.boff
+
+proc fireRow*(f: AimFire): JsonNode =
+  ## The `aim_fire` line.
+  result = newJObject()
+  result[FireRecordKey] = newJObject()
+  let b = result[FireRecordKey]
+  b["tick"] = %f.tick
+  b["eid"] = %f.eid
+  b["gun"] = %f.gun
+  b["power"] = %f.power
+  b["aim"] = %f.aim
+  b["turret"] = %f.turret
+  b["terr"] = %f.terr
+  b["heat"] = %f.heat
+  b["ax"] = %f.ax
+  b["ay"] = %f.ay
+  b["tof"] = %f.tof
+  b["ex"] = %f.ex
+  b["ey"] = %f.ey
+  b["eh"] = %f.eh
+  b["es"] = %f.es
+  b["ee"] = %f.ee
+  b["sx"] = %f.sx
+  b["sy"] = %f.sy
+  b["lst"] = %f.lst
+
+proc appendLine*(path: string, row: JsonNode) =
+  ## Append one JSONL line, fully guarded: a full disk or a bad path must
+  ## never take the bot down (same contract as the existing recorders).
+  try:
+    let f = open(path, fmAppend)
+    f.writeLine($row)
+    f.close()
+  except CatchableError:
+    discard
@@ -52,6 +52,7 @@ type
    vBulletDebugGun*:  string
    vBulletDebugMax*:  int
    recordWorldState*: bool
+    captureAim*:       bool  ## j177: aim_scan / aim_fire records, default off
    geoDebug*:         bool
    debugDraw*:        bool
    radarForceSpin*:   bool
@@ -245,6 +246,8 @@ proc printEffectiveValues(ctx: EnvReportContext) =
  emit("TR_RESULT_LOG", onOff(ctx.resultLog), sourceOf("TR_RESULT_LOG"))
  emit("TR_RECORD_WORLDSTATE", onOff(ctx.recordWorldState),
       sourceOfPresence("TR_RECORD_WORLDSTATE"))
+  emit("TR_CAPTURE_AIM", onOff(ctx.captureAim),
+       sourceOfPresence("TR_CAPTURE_AIM"))
  emit("TR_RADAR_FORCE_SPIN", onOff(ctx.radarForceSpin),
       sourceOfPresence("TR_RADAR_FORCE_SPIN"))
  emit("TR_RADAR_SCANLOG", onOff(ctx.radarScanLog),
@@ -657,7 +660,7 @@ proc knownEnvNames*(): seq[string] =
    "GUN_SELECTOR_SHRINK", "GUN_SELECTOR_DWELL", "GUN_SELECTOR_MARGIN",
    "GUN_SELECTOR_POINT_TIE", "GUN_SELECTOR_SEED",
    "GUN_RACK_DISABLE", "GUN_STATS_PATH", "GUN_SHOTLOG_PATH",
-    "TR_MOVEMENT", "TR_MOVEMENT_LOG", "TR_RECORD_WORLDSTATE",
+    "TR_MOVEMENT", "TR_MOVEMENT_LOG", "TR_RECORD_WORLDSTATE", "TR_CAPTURE_AIM",
    "TR_RADAR_FORCE_SPIN", "TR_RADAR_SCANLOG", "TR_RADAR_SCAN_LOG_PATH",
    "TR_TRACKER_PROBE", "TR_TRACKER_PROBE_PATH", "TR_VBULLET_ADMIT_ONLY",
    VBulletDebugEnv, VBulletDebugGunEnv, VBulletDebugMaxEnv,
@@ -23,6 +23,8 @@
 ##   A trailing live end marker is also optional:
 ##     {"end":{"enemy_died":<bool>,"ticks":<int>}}
 ##   It lets the replay reproduce the live resolver's final-tick behaviour.
+##   `aim_scan` / `aim_fire` annotation lines (written only when
+##   TR_CAPTURE_AIM is set) carry no `ex` and are skipped.
 ##
 ## The replay never calls the gun selector, so it is RNG-free for every
 ## deterministic gun. Tsetlin is stochastic and is expected to differ.
@@ -196,6 +198,10 @@ proc loadFixture*(path: string): Fixture =
      if node["end"].hasKey("enemy_died"):
        result.enemyDied = node["end"]["enemy_died"].getBool()
      continue
+    # j177: the recorder can also write `aim_scan` / `aim_fire` lines into the
+    # same file when TR_CAPTURE_AIM is set. They are annotations on ticks, not
+    # ticks, so they carry no `ex` and are skipped here.
+    if not node.hasKey("ex"): continue
    result.states.add stateFromJson(node, arenaW, arenaH, enemyId)
    result.lastSeen.add (if node.hasKey("lst"): node["lst"].getInt() else: -1)
  result.enemyId = enemyId
@@ -0,0 +1,18 @@
+# j177 gun-path default-parity golden.
+# Generated from the PRE-CHANGE tree (`git archive 55e92bc`) with
+# TR_CAPTURE_AIM unset, over the whole tr_drussgt_vs_modularbot.jsonl.
+# Format: <gun> shots=<n> hits=<n>, one line per rack gun
+HeadOn shots=400 hits=59
+Linear shots=400 hits=47
+Tsetlin shots=400 hits=74
+Circular shots=400 hits=51
+GuessFactor shots=400 hits=44
+Pattern shots=400 hits=46
+WallBounce shots=400 hits=55
+Accel shots=400 hits=59
+StopShot shots=400 hits=84
+Displace shots=400 hits=46
+AvgLead shots=400 hits=51
+DecayGF shots=400 hits=47
+KNN shots=400 hits=29
+TMSelect shots=0 hits=0
@@ -0,0 +1,132 @@
+## j177 guard: the aim capture actually contains every field it promises, and
+## the default gun path is byte-for-byte unchanged.
+##
+## NO battle, NO Java, NO server, NO GUI.
+##   nim c -r --path:common_libs --path:ModularBot_garage/src \
+##          --nimcache:/tmp/nc_j177 common_libs/tests/test_aim_capture.nim
+##
+## Part 1 (the guard): with the capture ON, build one `aim_scan` and one
+## `aim_fire` row from a real recorded tick of
+## tools/fixtures/tr_drussgt_vs_modularbot.jsonl, through the SAME
+## `aim_capture` row builders ModularBot.nim calls, and assert every required
+## key is present and carries the value that was passed in. A capture that
+## silently omits a field is worse than none.
+##
+## Part 2 (default parity): replay the whole recorded fixture through the real
+## VirtualTracker + the guns with the capture OFF and compare the per-gun
+## fitness report against `fixtures/aim_capture_gunpath.golden`. That golden
+## was generated from the PRE-CHANGE tree (`git archive 55e92bc`) with the
+## knob unset — regenerating it from this code would defeat the check.
+## Part 2b: the same replay over a fixture that ALSO carries aim_scan/aim_fire
+## lines must give the identical report, i.e. the annotations are inert.
+
+import std/[json, os, strutils, sequtils, strformat]
+import gun_harness/offline_range
+import range_guns
+import ../../ModularBot_garage/src/aim_capture
+
+const
+  repoRoot   = currentSourcePath().parentDir.parentDir.parentDir
+  fixtureRel = "tr_drussgt_vs_modularbot.jsonl"
+  fixture    = repoRoot / "tools" / "fixtures" / fixtureRel
+  goldenPath = currentSourcePath().parentDir / "fixtures" / "aim_capture_gunpath.golden"
+  annotated  = "/tmp/j177_annotated_fixture.jsonl"
+  ScanKeys   = ["tick", "eid", "ex", "ey", "eh", "es", "ee", "sx", "sy", "sh", "ss",
+                "gun", "bx", "by", "bh", "bs", "blst", "age", "rlock", "rdir",
+                "lbear", "boff"]
+  FireKeys   = ["tick", "eid", "gun", "power", "aim", "turret", "terr", "heat",
+                "ax", "ay", "tof", "ex", "ey", "eh", "es", "ee", "sx", "sy", "lst"]
+
+var failures = 0
+proc check(name: string, ok: bool) =
+  if ok: echo "PASS: ", name
+  else:
+    echo "FAIL: ", name
+    inc failures
+
+proc replayReport(path: string): string =
+  ## Per-gun shots/hits over the whole fixture, through the REAL tracker and
+  ## the REAL guns, with the capture OFF.
+  let res = replayFixture(loadFixture(path), buildAllGunDrivers(seed = 1))
+  for r in res:
+    result.add r.name & " shots=" & $r.shots & " hits=" & $r.hits & "\n"
+
+# ── Part 1: the records carry every field ────────────────────────────────────
+proc fieldCheck() =
+  let states = loadFixture(fixture).states
+  check("fixture loaded", states.len > 1000)
+  let ws = states[900]
+  let scan = scanRow(AimScan(
+    tick: 900, eid: 7,
+    ex: ws.enemyX, ey: ws.enemyY, eh: ws.enemyHeading, es: ws.enemySpeed,
+    ee: ws.enemyEnergy, sx: ws.selfX, sy: ws.selfY, sh: ws.selfHeading,
+    ss: ws.selfSpeed, gun: 5,
+    bx: ws.enemyX - 8.0, by: ws.enemyY - 8.0, bh: ws.enemyHeading,
+    bs: ws.enemySpeed, blst: 896,
+    rlock: true, rdir: 42.5, lbear: bearing(ws.enemyX - 8, ws.enemyY - 8, ws.selfX, ws.selfY),
+    boff: -12.25))
+  let fire = fireRow(AimFire(
+    tick: 900, eid: 7, gun: 5, power: 1.6, aim: 88.25, turret: 74.0,
+    terr: 14.25, heat: 0.31, ax: ws.enemyX + 40.0, ay: ws.enemyY - 15.0,
+    tof: 12.5, ex: ws.enemyX, ey: ws.enemyY, eh: ws.enemyHeading,
+    es: ws.enemySpeed, ee: ws.enemyEnergy, sx: ws.selfX, sy: ws.selfY, lst: 897))
+
+  for k in ScanKeys:
+    check("aim_scan has " & k, scan[ScanRecordKey].hasKey(k))
+  for k in FireKeys:
+    check("aim_fire has " & k, fire[FireRecordKey].hasKey(k))
+
+  check("aim_scan carries the gun id", scan[ScanRecordKey]["gun"].getInt() == 5)
+  check("aim_fire carries the gun id", fire[FireRecordKey]["gun"].getInt() == 5)
+  check("aim_scan records the scan parity age",
+        scan[ScanRecordKey]["age"].getInt() == 4)
+  check("aim_fire records the source tick (parity)",
+        fire[FireRecordKey]["lst"].getInt() == 897)
+  check("aim_fire carries the aim angle", fire[FireRecordKey]["aim"].getFloat() == 88.25)
+  check("aim_fire carries the turret error", fire[FireRecordKey]["terr"].getFloat() == 14.25)
+  check("aim_fire carries the WorldState the model consumed",
+        fire[FireRecordKey]["ex"].getFloat() == ws.enemyX and
+        fire[FireRecordKey]["ey"].getFloat() == ws.enemyY)
+
+  echo "\n--- aim_scan record ---"
+  echo $scan
+  echo "--- aim_fire record ---"
+  echo $fire
+  echo ""
+
+# ── Part 2: default gun-path parity ──────────────────────────────────────────
+proc parityCheck() =
+  let clean = replayReport(fixture)
+  let ticks = loadFixture(fixture).states.len
+  if defined(aimCapGenGolden):
+    var g = "# j177 gun-path default-parity golden.\n"
+    g.add "# Generated from the PRE-CHANGE tree (`git archive 55e92bc`) with\n"
+    g.add "# TR_CAPTURE_AIM unset, over the whole " & fixtureRel & ".\n"
+    g.add "# Format: <gun> shots=<n> hits=<n>, one line per rack gun\n"
+    g.add clean
+    createDir(goldenPath.parentDir)
+    writeFile(goldenPath, g)
+    echo "wrote ", goldenPath, " (", ticks, " ticks)"
+    return
+  check("golden exists", fileExists(goldenPath))
+  if not fileExists(goldenPath): return
+  let g = lines(goldenPath).toSeq().filterIt(not it.startsWith("#")).join("\n").strip()
+  check("gun path byte-for-byte identical over " & $ticks & " ticks", g == clean.strip())
+
+  # 2b: the annotation lines must be inert for the replay.
+  let extra = @[
+    $scanRow(AimScan(tick: 0, eid: 1, ex: 1.0, ey: 2.0, eh: 3.0, es: 4.0, ee: 5.0,
+                     sx: 6.0, sy: 7.0, sh: 8.0, ss: 9.0, gun: 3,
+                     bx: 0.0, by: 0.0, blst: -1, rlock: true, rdir: 1.0, lbear: 2.0)),
+    $fireRow(AimFire(tick: 1, eid: 1, gun: 3, power: 1.5, aim: 1.0, turret: 2.0,
+                     terr: 3.0, heat: 0.0, ax: 1.0, ay: 1.0, tof: 1.0,
+                     ex: 1.0, ey: 1.0, eh: 1.0, es: 1.0, ee: 1.0,
+                     sx: 1.0, sy: 1.0, lst: 0))]
+  writeFile(annotated, (lines(fixture).toSeq() & extra).join("\n"))
+  check("aim records do not perturb the replay", replayReport(annotated) == clean)
+  removeFile(annotated)
+
+fieldCheck()
+parityCheck()
+echo (if failures == 0: "\nALL PASS" else: "\n" & $failures & " FAILURE(S)")
+quit(if failures == 0: 0 else: 1)
@@ -616,6 +616,7 @@ Measured byte-identical on `bmPath`. Kept for experiments; leave at defaults.
 | `TR_RADAR_SCAN_LOG_PATH` | `/tmp/radar_scan_log.jsonl` | where that goes |
 | `TR_TRACKER_PROBE` | off | presence-based; per-tick enemy tracker vs server enemy count |
 | `TR_TRACKER_PROBE_PATH` | `/tmp/tracker_probe.jsonl` | where that goes |
+| `TR_CAPTURE_AIM` | off | presence-based; append `aim_scan` / `aim_fire` records — what the lead model BELIEVED (gun id, blst, age, boff, aim, turret, terr, heat, ax/ay, tof) to the same capture file as `TR_RECORD_WORLDSTATE` (needs `TR_RECORD_WORLDSTATE=1`) |
 | `TR_VBULLET_DEBUG` | off | presence-based; overlay the virtual bullets in the GUI debug graphics (see below) |
 | `TR_VBULLET_DEBUG_GUN` | selected gun | `all`/`*` for every gun, or a gun name (e.g. `Pattern`); unset = only the currently selected gun |
 | `TR_VBULLET_DEBUG_MAX` | `32` | cap on bullets drawn per tick |
@@ -633,6 +634,21 @@ selector's training signal visible. Turn it on with:
 - colour per gun is the SAME table as the turret (`vbullet_draw.gunColors`), with
  a one-line legend in the top-left corner.

+### Known limitations — `TR_CAPTURE_AIM` (j177)
+
+**`aim_fire` only records shots that PASSED `setFire`.** The capture is written
+from the bot's own fire call, so a shot the **server rejected or that the bot
+never issued** produces no `aim_fire` record at all.
+
+That is a real blind spot: from these records you can never answer *why* a shot
+did not happen — e.g. the gun was still hot, or the turret was not yet aligned.
+A missing `aim_fire` is ambiguous between "no target / didn't try" and "tried and
+was refused". The `aim_scan` records carry the belief state (age, boff, turret,
+heat) for every scan, so you can often *infer* the cause by looking at the scans
+that precede the gap, but the capture does not state it. Read the gaps as
+"no recorded shot", never as "the server blocked it". Closing this needs a
+pre-`setFire` gate record, which is j177+ work, not present today.
+
 The **adaptive-melee radar** has no env knobs. Its tuning lives in compile-time
 constants in `radars/adaptive_melee_radar.nim:36-50`: `MaxRadarTurnRate=45`,
 `FreshnessTicks=16`, `FreshStreakTicks=3`, `MarginDeg=20`,
@@ -0,0 +1,283 @@
+# Range vs approach: melee is unavailable against DrussGT, so the gun at range is the only lever
+
+**Date:** 2026-09-27 · **Job:** j167 · **Branch:** `research/lead-targeting`
+**Evidence base:** j166 (`worktrees/j166-aim` @ `a5a49bd`), j165 (`fe77056`), j159
+(`4a1f3e1`), j165/j151/j152/j154, j160/j163 (`0df7763` / `51bfa57`), j161
+(`docs/ram_floor_exhaustion_ab.md:219`).
+**Instrument for the new numbers below:** `worktrees/j167-ceiling/j167_probe.py`
+(branch `j167-ceiling`) — pure replay of the recorded corpora
+(`/tmp/tfil_ab2/out/`, 60 252 of our own scored shots over 140 battles; and
+`/tmp/firelag_live2/`, 1 700 shots / 1 664 incoming bullets over 4 battles).
+**No battle, A/B, server or GUI was run for this document.**
+
+---
+
+## 1. The ceiling
+
+**Melee is structurally unavailable against DrussGT, and the exhaust/ram line is a
+niche rather than a lever.** The evidence is two-sided and independent: (a) *our
+mover's own ruler* — 94% of forced (no-safe-tile) picks happen at range > 300 u
+and only 6-7% of picks reach the chosen tile at the estimated arrival time, with
+the destination hot on arrival 35-42% of the time; and (b) *the j166 pursuit
+probe* — 35 windows × 250 ticks of open-loop kinematics in which **every**
+steering law is equal-or-worse than doing nothing clever:
+
+| steering law (j166) | closing (u/tick) | contact % | TTI (ticks) |
+|---|---:|---:|---:|
+| current-position closing | 4.03 | 65.7 | 72.3 |
+| body/barrel ray | 1.38 | 40.0 | 131.4 |
+| velocity intercept (degenerate at equal speed) | — | 0 over 2 118 ticks | — |
+| best case: lag-5 lead | 4.20 | 65.7 | 68.9 |
+
+The root cause of the historical **0/59 proactive-ram** result
+(`docs/ramming_negative_result.md`) is not a bad gate: **DrussGT never let the
+distance drop.** Per-round minimum distance 152-338 u, median ~490 u, and
+`frac(dist < 50) = 0.000` in all four recorded rounds. A pursuit that never gets
+below 152 u cannot make contact, whatever the gate says. It is also not a
+gun-side problem: **the server never transmits the enemy's gun direction**
+(`ScannedBotEvent` = `energy, x, y, direction` where `direction` is the BODY
+heading, plus `speed`; `TurnProcessor.kt:313-323`). There is no aim-based lead,
+no aim-based dodge and no early warning available. Against DrussGT the
+body-to-bullet angle has median **90.1 deg**, and the body ray passes within
+10 deg of us on **0.0% of 1 794 ticks** — its gun is always on us, its body
+never is.
+
+**Recorded so the idea is not re-proposed:** the j166 lag-5 residue does improve
+TTI (72.3 → 68.9) and **converts to contact 0% of the time**. A 4% TTI gain with
+zero contact conversion is noise, not a lead.
+
+### The honest remaining niches for exhaust/ram
+
+1. **An opponent that closes on us.** Ram works whenever the other side comes to
+   us. Nothing here generalises away from that.
+2. **A late-round exhaustion when they are already near.** The one conversion
+   ever recorded came from a *finisher* (enemy 16 → 1 energy), which is already
+   the default gate.
+3. **Any 2v1+ mode**, where closing dynamics are not symmetric.
+
+Against DrussGT specifically none of these will move the score, and
+`TR_RAM_FLOOR_ENERGY` is under test in j163 — do not duplicate it.
+
+---
+
+## 2. What the ceiling implies
+
+**If range is held, the only remaining lever is the gun at range, and the binding
+numbers are the gun's, not the tile picker's.** The long-range hit rate is
+**~9-10%** (Pattern live: 12.3% at 300-450 px, 9.2% at 450+; overall 10.5% —
+`docs/headon_longrange_live.md`), the live hit half-window at 450 px is
+**`atan(18/450) = 2.29°`** (`docs/gun_campaign.md:59`), and the measured arrival
+aim error is **16.19° mean-abs at 450+** (`docs/bitbrain_campaign.md:107`,
+`docs/headon_longrange_live.md:85`). 16.19° is **7× the window**. The tile picker
+cannot close a 7× gap that sits downstream of the gun.
+
+### New measurement — arrival aim error decomposed (j167, 23 275 shots at 450+ px)
+
+Arrival aim error is defined non-circularly: the angle between the fired bearing
+and the bearing to where the target *actually is* when the bullet arrives
+(`tof = 20 - 3·power`, so the flight time comes from the power, not from the
+shot's own geometry). It splits **exactly**, as signed angles, into
+
+* **B, the model part** = the error the gun's own lead model leaves behind, and
+* **C, manoeuvre** = the target's path curvature relative to the
+  constant-velocity extrapolation from the true state at fire time.
+
+| band (px) | n | mean&#124;A&#124; | mean&#124;B&#124; (model) | mean&#124;C&#124; (manoeuvre) | sd(B) | sd(C) | corr(B,C) |
+|---|---:|---:|---:|---:|---:|---:|---:|
+| 0-100 | 24 767 | 83.36 | 101.56 | 49.38 | 124.5 | 75.9 | −0.65 |
+| 300-450 | 11 372 | 13.07 | 21.77 | 11.00 | 26.0 | 13.0 | −0.87 |
+| **450+** | **23 275** | **11.26** | **17.18** | **7.73** | **20.7** | **9.3** | **−0.85** |
+
+At 450+ the model part's variance is **2.2× the manoeuvre part's**, and
+`corr(B,C) = −0.85` means the two largely *cancel* — the net 11.26° is much
+smaller than either part. **The 16° is a lead-model number, not a dodge number.**
+Two supporting numbers: a naive constant-velocity extrapolation of a **2-tick-old**
+position scores 8.45° mean-abs at 450+, and the time-of-flight implied by the
+shot's own geometry (holding the current velocity) sits a **median 10 ticks short**
+of the power-derived arrival tick (p10 −18, p90 +31) — i.e. the gun systematically
+**under-leads in time**, consistent with `docs/lead_capture_by_range.md`
+(capture 0.135 at 450+).
+
+> **Do not read "a stale-CV model scores 8.45°" as "simplify the gun".** This is
+> exactly the offline-ruler trap that killed HeadOn: the ruler said a no-lead gun
+> was equal-or-better at 300+ and live it hit **20×/23× less**
+> (`docs/headon_longrange_live.md`). The corpus is closed-loop — the target's
+> manoeuvre is a *reaction to our own bullet* — so (B) and (C) are not separable
+> here, and per `docs/offline_harness_trust.md` (j89: 0/6 on closed-loop) this
+> instrument ranks per-gun single-tick prediction, it does not predict a live A/B.
+
+### Cross-reference: what is still open in the gun docs
+
+| doc | finding | status after this ceiling |
+|---|---|---|
+| `docs/gun_campaign.md:59` | hit half-window 2.29° at 450 px; measured signal 4.6-7.6° | **STILL OPEN and now the load-bearing number.** The decomposition says the gap is in the *model*, and the model is systematically 10 ticks short in time-of-flight. |
+| `docs/gun_campaign.md:40-45` | lead amplitude is dead (1.0/1.5/2.0/3.0 all worse); radial knobs are bearing-invariant by construction | **CLOSED.** |
+| `docs/gun_campaign.md:737-753` | `len6` +0.49 wins/run (p=0.039, n=15) did not replicate on n=33 | **CLOSED.** |
+| `docs/bitbrain_campaign.md:189` | BitBrain / TMHorizon corrector adds no measurable aim (16.199 vs 16.193) | **CLOSED.** |
+| `docs/bitbrain_campaign.md:107` | Pattern's own lead correlation with the required lead is 0.165 at 450+ | **STILL OPEN.** It is the same defect the decomposition names. |
+| `docs/state_window_gate.md` | single wave-relative state at Q=4 predicts the miss bin at 0.4094 vs 0.2348 majority, but bins are 4.58-7.63° wide | **STILL OPEN, and now the best-placed surviving idea** — it is a *model* correction, which is where the error is. |
+| `docs/gun_rack_analysis.md:423-455` | the 16-candidate rack ranking A/B found no winner; knobs added, all neutral | **CLOSED** (13 guns, `onlyPattern` shipped). |
+
+---
+
+## 3. Negative-results ledger — mechanisms closed by measurement
+
+Do not re-litigate any row. The unit of evidence is the **opponent**.
+
+| mechanism | knob / job | headline number | verdict |
+|---|---|---|---|
+| Geometry-weighted tile draw | `TR_TFIL_GEO_MODE/TAU`, j152 `38fbc6e`, A/B'd j159 `4a1f3e1` | **−8.83 damage/run, p=0.0061**; wins −0.05, p=0.46; +26.3 px mean distance on 15/15 opponents | **REJECTED.** Default off, stays off. |
+| The bounded hold | `TR_TFIL_HOLD_MAX_TICKS`, j154 `2223ca6` | mechanism-positive, outcome-null (j146/j153) | **Default off.** No live win. |
+| The proactive ram | `oldram` vs `base` gate `dist<200` | **p=0.69**, damage 279 vs 284, survival 17/49 vs 16/49; **0/59 opportunity→contact** | **CLOSED** (`docs/ramming_negative_result.md`). |
+| The aim-based ram | j166 `a5a49bd` | body ray within 10° of us on **0.0% of 1 794 ticks**; body/barrel ray contact 40.0% vs 65.7% for doing nothing clever | **IMPOSSIBLE** — the server never sends gun direction (`TurnProcessor.kt:313-323`). |
+| Arrival commitment (`tfil`) | j144 `d2005ab` | mechanism-positive, outcome-null | Default off. |
+| Turn-cost tiebreak among safe tiles | j145 `39c90fd` | real but small mechanism, under-powered outcome null (300 battles, 5 arms) | Default off. |
+| Field shape (safety) | j146 `de5d02b` | safe-set broken 63.5% → 30.4% offline; live null on damage and wins (375 battles, 5 arms) | **Default off.** |
+| Corridor bound | j148 `5e213df` `TR_{TFIL,STRAFE}_CORRIDOR_TICKS` | never landed in a live A/B | Untested, not a candidate. |
+| Ring arrival commitment | j165 `fe77056` `TR_TFIL_RING_COMMIT_ARRIVAL` | reach 0.24% → **3.05%**, picks 5 521 → 525, byte-for-byte default parity over 20 026 ticks, 148 guards | **Mechanism-positive, default off.** The strongest surviving movement mechanism. |
+| Firing floor / enemy-exhaustion ram | j160 `23bce2d`, A/B'd j163 `51bfa57` | **clean negative**; the offline energy corpus missed the live game by 200× | **Under test in j163 — do not duplicate.** |
+| Fire-detection lag | j147 `d21f7ce` `TR_FIRE_LAG` | displacement 19.06 → 5.37 px, deadline error 0.99 → 0.06 ticks; **live outcome-neutral**; ceiling ~10% of incoming damage (measured below) | **Default off, permanently.** |
+| Hard arrival bound | j151 `a01141c` `TR_TFIL_ARRIVE_TICKS` | mechanism-positive, outcome-null | Default off. |
+
+> **Methodological caution (j161), binding on everything above.** Pooled tests
+> can hide real per-opponent effects: j159's safety signal was **p=0.0008
+> per-opponent while the pooled test was null** (`docs/ram_floor_exhaustion_ab.md:219`).
+> **Any future mechanism claim must report per-opponent mechanism metrics, not a
+> pooled mean.** A pooled null is not evidence of absence; it is evidence that
+> the heterogeneity was not averaged down.
+
+---
+
+## 4. Lead-time lever 1 — what a 2-tick-stale ghost really costs
+
+`TR_FIRE_LAG` back-dates the bullet ghost (default 0). Energy-drop shot
+detection lags **1.9 ticks mean**; median bullet flight is **19 ticks**
+(`onHitByBullet` gives 82 hits / 7 421 ticks, one update per ~90 ticks).
+
+**Measured on 55 750 incoming bullets** (`/tmp/tfil_ab2/out/`). For each bullet:
+the time to closest approach of the target's recorded path to the bullet line
+(**median 9 ticks**, p10 1, p90 39), and the minimum number of ticks of lead time
+a max-speed hard-turn dodge needs to build 17 px of lateral displacement:
+
+| minimum dodge lead time (ticks) | 0 | 1 | 2 | 3 | 4 | 5+ |
+|---|---:|---:|---:|---:|---:|---:|
+| share of incoming bullets | **57%** | 33% | 4% | 2% | 1% | 2% |
+
+**57% of incoming bullets are already undodgeable at the instant they are fired**,
+and only **~10%** (need ≥ 2 ticks) are in a regime where a 2-tick detection lag
+can change anything. Applying the lag to the open-loop dodge model:
+
+| ghost lag (ticks) | modelled hits | Δ vs perfect | share of all bullets whose hit/miss verdict flips |
+|---|---:|---:|---:|
+| 0 | 22 419 | — | — |
+| **1.9 / 2** | **25 100** | **+2 681 (+12.0%)** | **10.18%** |
+| 3 | 26 230 | +14.6% | 14.63% |
+| 5 | 28 949 | +22.0% | 22.04% |
+
+**Verdict: the 1.9-tick lag costs on the order of 10% more incoming hits** — at
+the measured ~200 damage/run, roughly **20 damage/run**, an order of magnitude
+below the movement A/B damage MDE. This is consistent with `TR_FIRE_LAG`'s already
+measured live outcome-neutral result. The ghost is *wrong*, but wrongness at
+10% of incoming damage cannot be turned into wins at this sample size.
+
+**Recommendation: `TR_FIRE_LAG` stays off permanently.** It is a correctness fix
+with a measured, bounded, sub-MDE payoff.
+
+---
+
+## 5. Lead-time lever 2 — the 16° decomposed, component by component
+
+At 450+ px (23 275 shots), against the 11.26° net arrival error:
+
+| component | measured | addressable? |
+|---|---|---|
+| **(a) enemy body-gun decoupling** | `\|gun dir − body heading\|` median **89.9°** (p10 25.9, p90 154.0, n=60 928). Extrapolating the target along its **gun** instead of its **body** would put the arrival bearing **79.5° median** wrong. | **Not present, and not addressable.** The intercept model uses the target's *recorded position and velocity*, both of which are the true body quantities and both exactly observed. Body-gun decoupling therefore contributes **exactly 0** to our arrival error. It is fatal for *aim-based* leading and threat warning (j166) and irrelevant to *position-based* leading. |
+| **(b) our own leading model** | mean&#124;·&#124; **17.18°**, sd **20.7**; implied time-of-flight a **median 10 ticks short** of the power-derived arrival tick | **DOMINANT, and addressable.** This is ~2.2× the manoeuvre variance and it is the whole of the 16°. |
+| **(c) target manoeuvre between scan and fire** | mean&#124;·&#124; **7.73°**, sd **9.3** | Small relative to (b), and **irreducible** — it is the dodger's own unpredictability, exactly the ~half of the under-lead `docs/lead_capture_by_range.md` attributes to a trivial predictor's own ceiling. |
+| **(d) gun turn rate / time-to-fire** | the correct solution drifts a **median 0.416°/tick** (p90 5.45). The gun turns at 10°/tick, so a 17° correction takes **1.7 ticks ≈ 0.40°** of drift. | **Not binding.** Contributes ~**0.4°, i.e. ~3% of the 11.26° error.** The gun can always reach the answer; it aims at the wrong answer. |
+
+**So the 16° is not (a), not (c) and not (d). It is (b) — the lead model's
+time-of-flight, short by ~10 ticks.** Caveat, stated once and load-bearing: on a
+closed-loop corpus (B) and (C) are not cleanly separable, since the target's
+manoeuvre is a reaction to our own shot; the `corr(B,C) = −0.85` is exactly that
+confound showing up. The *rank order* (b) ≫ (c) ≫ (d) > (a)=0 is robust to it
+because (b) and (c) differ by 2.2× in variance and (d) is 3%.
+
+---
+
+## 6. The proposed lever: pre-multiply before learning — PREMISE DEAD
+
+The design: aim error is largely a *product* (bearing-rate × time-of-flight), so
+pre-multiply the two features and feed one small Tsetlin machine. **Measured on
+the same corpus, the premise does not hold and the experiment should not be
+built.** `y` = the required lead angle (current bearing → arrival bearing), i.e.
+exactly the quantity the gun must predict; `b` = the observable 4-tick finite
+difference of the bearing; `t = 20 − 3·power`.
+
+| band (px) | n | corr(**b·t**, y) | corr(b+t, y) | R² additive [1,b,t] | R² product [1,b·t] | held-out side acc, additive | held-out side acc, product | held-out residual rms (deg) |
+|---|---:|---:|---:|---:|---:|---:|---:|---:|
+| 0-200 | 24 934 | −0.1020 | −0.1022 | 0.0105 | 0.0104 | 0.579 | 0.580 | 75.98 |
+| 200-300 | 671 | 0.1190 | 0.0766 | 0.0147 | 0.0142 | 0.488 | 0.487 | 13.70 |
+| 300-450 | 11 372 | **0.1501** | 0.0299 | 0.0256 | 0.0225 | 0.544 | 0.534 | 8.43 |
+| **450+** | **23 275** | **0.2833** | 0.1052 | **0.0831** | 0.0803 | **0.603** | **0.601** | **6.68** |
+| pooled | 60 252 | −0.1005 | −0.1009 | 0.0102 | 0.0101 | — | — | — |
+
+*(side accuracy is 2-fold held-out and balanced; the TM record is ~0.47-0.49)*
+
+Two things are true and the second kills the idea:
+
+1. **As a single scalar, the product is much the better feature at range**:
+   `corr(b·t, y) = 0.283` vs `corr(b+t, y) = 0.105` at 450+ — 2.7× better, and
+   5× better at 300-450. So the *premise* ("the error is a product, not a sum")
+   is **confirmed as a statement about correlation**.
+2. **But it buys nothing a weight-sum cannot already express.** The best linear
+   additive model on the same two features reaches **R² 0.0831 vs the product's
+   0.0803**, and the held-out balanced side accuracy is **0.603 (additive) vs
+   0.601 (product)** — a 0.002 difference, i.e. nothing. Pooled, the two are
+   identical (−0.1005 vs −0.1009; R² 0.0102 vs 0.0101). A TM with two input
+   features **already reconstructs the product term**; the multiplication is what
+   the network was doing anyway.
+
+**Even the ceiling is out of reach.** The best held-out residual on the required
+lead at 450+ is **6.68° rms**, against a live hit half-window of **2.29°** — a
+2.9× shortfall. Pre-multiplying does not get a classifier to 2.29°; nothing in
+this family does. **Do not build it.** The spec is recorded here so the idea is
+closed on measurement rather than on taste.
+
+*(Had it survived, the spec would have been: one TM, ONE input feature `b·t`
+binarised on sign, plus the 4-bit horizon one-hot as today; offline gate =
+held-out balanced side accuracy above 0.55 and residual rms below 3° at 450+;
+live gate = wins/run with CI excluding 0 and sign-flip p<0.05 at 210 runs/arm,
+damage not detectably down, MDE 0.17 wins/run. Predicted accuracy was 0.60 side
+accuracy, which is a real signal against the 0.47-0.49 record — and still not
+close enough to the window to convert.)*
+
+---
+
+## 7. The A/B queue, in priority order, with the MDE honestly restated
+
+Throughput **22.7-23.2 runs/min**; movement gate resolved **0.17 wins/run at 210
+runs/arm**; the `1/√n` extrapolation to 0.10 wins/run is **607 runs/arm ≈ 1.4 h —
+a FLOOR on elapsed time, not an estimate**, because opponent heterogeneity does
+not average down. A null at this sample size **only excludes a LARGE effect.**
+(j163 additionally measured 14-22 runs/min, not 22.7-23.2, so even the floor is
+optimistic.)
+
+| # | experiment | what it tests | cost | a null would license |
+|---|---|---|---|---|
+| **1** | **The lead-model time-of-flight correction** (j167's (b)): re-derive the gun's arrival prediction so the implied flight is the power-derived tick, not 10 ticks short. | The one component that carries 2.2× the error variance at 450+, and the only open axis in `docs/gun_campaign.md` (lead *information*, not amplitude). | Offline gate first: arrival aim error at 450+ must fall below 11.26° mean-abs on held-out battles, ideally <8°; only then 2 arms × 15 opponents × 14 runs = 420 battles ≈ **0.3-0.4 h** wall. | Closing the single open gun axis. Nothing left in the gun. |
+| 2 | `TR_TFIL_RING_COMMIT_ARRIVAL` (j165, default off) | Whether the largest surviving *movement* mechanism (reach 0.24% → 3.05%, picks 5 521 → 525, 148 guards) converts to wins. | 210 runs/arm ≈ **1.4 h floor**. | Retiring the whole ring/approach programme: if even a 12× reach gain is outcome-null, the ceiling argument is confirmed end to end. |
+| 3 | `TR_FIRE_LAG` (tfil/strafe, default off) | Nothing worth testing — its ceiling is now measured at **~10% of incoming damage ≈ 20 dmg/run**, below the MDE. | Would be 1.4 h to learn nothing. | Nothing. **Skip it**; the measurement has already answered it. |
+| 4 | `TR_TFIL_ARRIVE_TICKS` (j151, default off) | Whether a hard arrival bound converts now that the ring is rehabilitated. | 1.4 h. | Retiring it with j151's own null attached. |
+| 5 | `TR_RAM_FLOOR_ENERGY` (j160, j163) | **Under test in j163. DO NOT DUPLICATE.** | — | — |
+
+**Recommendation.** Run **only experiment 1**, and only after the *offline* gate
+passes; if the offline gate does not move the 450+ arrival error below ~8°, run
+nothing at all. Given five consecutive nulls or near-nulls (j144, j145, j146,
+j147, j159) plus a clean negative in j163, spending 1.4 h of live time on
+experiments 2-4 is not justified — those are mechanism-positive
+mechanisms whose outcome nulls are already the standing record, and a null there
+teaches nothing that the ledger does not already say.
+
+**"The ceiling is real and we should stop spending on movement" is the answer.**
+The remaining budget belongs to the gun's lead model, or it is not spent.