Follow-up to 9cd6e9b, which found the LINEAR base systematically overshoots (mean
radial error -71..-100px, enemy nearer in 63-81% of shots). The question was
whether the gun that actually ships, `Pattern`, overshoots too - because
correcting a systematic bias would be a cheap win.
1. PATTERN DOES NOT OVERSHOOT. Measured over the DrussGT fixtures (n=250,989):
Pattern mean -12.0 px, median -3.2 px, nearer 52.8% / farther 45.0%
Linear mean -87.3 px, median -61.0 px, nearer 83.4% / farther 14.4% (same states)
So the overshoot was a property of the CONSTANT-VELOCITY BASE, not of our
predictions in general. Pattern's pattern-matching does not have it, so there
was nothing to correct. (All-10-fixture pooled: mean -14.0, median -4.2.)
2. THE AVENUE IS STRUCTURALLY DEAD, not merely unprofitable. The live aim is
`aimAngle(self, pred)` and a RADIAL-only offset keeps the BEARING unchanged
(proven exactly by a guard test: bearing is invariant). So a radial offset
cannot change the fired bullet's direction at all. `bmPath` never scores the
aim distance either - and measured, every offset arm is BYTE-IDENTICAL to plain
Pattern on bmPath (33.9%/25.6%). The only real-effect channel is the `shouldFire`
gate via `distPx`, which is indistinguishable from noise.
3. LIVE A/B CONFIRMS: one frozen binary (built from HEAD + only this change),
env-only arms, 7 runs x 7 rounds, 8 concurrent, real DrussGT, server-side hit
rate, exact two-sided permutation test.
control (plain Pattern) 10.61% / 284 dmg-per-run
s0.98 10.89% / 302 (+0.28pp, p=0.62)
s0.95 10.02% (p=0.35)
o-20 10.19% (p=0.46)
No significant winner.
VERDICT: STOP. This line cannot help the shipped configuration, and the reason is
structural rather than statistical - a radial correction is bearing-invariant, so
it is invisible to the actual shot. The bmPoint "win" the radial TM showed was a
metric artefact of that same irrelevance.
Incidental: the control arm (10.61% / 284) independently replicates the shipped
Pattern-only default's A/B numbers (10.36% / 264, 10.78% / 287, 9.99%).
Kept anyway: `TR_PATTERN_RAD_SCALE` / `TR_PATTERN_RAD_OFFSET` default to
(1.0, 0.0) and the default path is byte-identical (proven over 2400 predictions,
plus bearing invariance and unparsable-value fallback - 6 checks). Adds
measure_pattern_radial.nim, sweep_pattern_radial.nim, test_pattern_radial_offset.nim
and pattern_radial_results.md.
Guards: test_gun_harness 39, test_vbullet_metric 11, test_power_selection 3,
test_adaptive_radar 41, test_tfil_ring_weights 24, test_power_policy 26,
test_ram_decision 28, test_rack_membership 48, test_tm_pattern_registration 20,
acceptance_offline_vs_online 12/12 PASS.
