#137 FIXED: restore the binary Reset's +0x58c re-seed -- the respawn freeze was a

teleport-poisoned finite difference, not heat, not the reset, not velocity

The one-line fix is the binary's own SECOND Reset instruction, dropped in
transcription:  FUN_00408440(mech+0x58c, param_2)  ==
    accelPrevPos = origin.linearPosition;
+0x58c is the previous-position memory of the AccelerationLastFrame ring feed
(+0x81c/0x824/0x828/0x82c).  The port reconstructed the ring faithfully (ctor
part_012.c:9836, derivative :15169) but Reset never re-seeded its cache, so the
first post-respawn sample computed |newPos - prevPos|/dt = TELEPORT DISTANCE/dt
(~1e5) into the velocity ring; the ring-mean derivative spiked
AccelerationLastFrame (pure forward, with an opposite-sign echo ~15 frames later
as the sample rotated out of the 15-ring); and the myomer integrator @004b8d18
turned it into a one-tick pendingHeat deposit of ~3e9:
    termAccel = (1-accEff) * |v| * |a| * m * dt
      = 0.2 * 40 * 1.04e5 * 75000 * 0.044  =  2.75e9
snapping the freshly-reset myomers from T=77 to T~9000 against failT=2000 ->
speedEffect 0 -> speedDemand *= 0 -> "respawned unable to move until it cools".

WHY ~8% IN THE FIELD: the deposit needs |v| in the same 1-2 frames, so only
pilots whose throttle was still forward at the respawn -- physical lever /
HOTAS, exactly who reported it -- had gait-republished speed in the spike
frames.  Idle-throttle respawns deposit ~nothing.  (And frozen-subset-of-
died-hot: died hot == was running hard == lever still forward.)

MEASURED, same abusive bench (0.95 throttle + continuous autofire):
    before: deposits up to 3.35e9, every one 3-4 lines after a Mech::Reset;
            4-6 of 7 respawns frozen; post-reset myomers T 7700-12100
    after:  deposits >1e7: ZERO across 7 respawns; frozen: ZERO;
            post-reset myomers T 77-178 (vs degradeT=1000)

THEORIES KILLED ON THE WAY, each by operand data, in order:
  * stale pendingHeat carryover (bounded to 1 frame, +1.2K -- gates agent)
  * slow accumulation during the death window (consumers tick the wreck)
  * conduction from a hot neighbour (roster-wide snapshot: ALL partners 77;
    flow trap: zero e6 flows into the myomers, ever)
  * drag/impulse writers (both trapped: never fired)
  * my own earlier "velocity-driven, players accelerate to top speed" close of
    the ticket -- arithmetically impossible (input ceiling ~6.5e5/frame ~=
    60 deg/s; the observed snap was 1,100-21,000 deg/s) and corrected in
    context/subsystems.md, which carried the wrong paragraph.
  * the localAcceleration zero-fill (+0x1dc) restored along the way is KEPT --
    the binary does it -- but it was NOT the cause; the snapshot is rebuilt
    from the position difference one frame later.

Probes kept (all BT_HEAT_LOG-gated): roster-wide [myofreeze] at-death/at-reset/
post-reset (T + heatEnergy + pendingHeat per subsystem), the [heatflow]
conduction trap with full operands, the [myodep] deposit trap with mech
identity + acceleration components.  Engine MOVER.cpp traps reverted -- they
proved their negative (drag/impulse innocent) and do not belong in engine
source.

Gotcha #30 records the class: when the binary's Reset writes a cell you don't
recognize, that write IS the spec -- transcribe the whole zero/seed list; any
prev-value cell backing a finite difference must be re-seeded at every
teleport; and derived state (T) sampled at the reset proves nothing about the
backing producers.

The operator called the shape of this two days ago: "maybe the math gets screwy
in respawning while some systems are ticking while values are being reset."
That is precisely what it was.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018SgmXGNMXavXiafKXf9MDC

context/reconstruction-gotchas.md

@@ -966,3 +966,34 @@ Rules:
     `[perf-first]` (one-shot per mech: entity ID + instance at its FIRST
     performance). Anonymous per-frame receipts are useless in a 2-node log —
     **name the mech.**
+
+## 30. A finite-difference cache the binary re-seeds at Reset — transcribe the WHOLE seed list (#137, 2026-08-09)
+
+The binary `Mech::Reset @0049fb74` opens with more than the obvious origin writes: its SECOND
+instruction is `FUN_00408440(mech+0x58c, param_2)` — re-seeding the **previous-position memory**
+of the AccelerationLastFrame ring feed (+0x81c/0x824/0x828/0x82c) to the new origin. The port
+reconstructed the ring itself faithfully (ctor `part_012.c:9836`, derivative `:15169`) but its
+Reset never got that one line. Result: the first post-respawn sample computed
+`|newPos − prevPos| / dt` = **teleport distance / dt ≈ 1e5** into the velocity ring; the
+ring-mean derivative turned it into an acceleration spike (with an opposite-sign ECHO ~15 frames
+later as the sample rotated out of the mean); the myomer heat integrator's
+`termAccel = (1−accEff)·|v|·|a|·m·dt` turned THAT into a ~3e9 one-tick heat deposit; and the
+freshly-reset myomers snapped from 77 to ~9000 against failT=2000 — the #137 respawn freeze.
+
+Rules:
+(a) **When the binary's Reset writes a cell you don't recognize, that write IS the spec.** The
+    +0x58c re-seed looked like bookkeeping and was silently dropped; it was the only thing
+    standing between a teleport and a position-derivative spike. Transcribe the whole zero/seed
+    list, then map each cell — never the recognizable subset.
+(b) **Any prev-value cell backing a finite difference must be re-seeded at every discontinuity**
+    (teleport, warp, respawn). If you add such a cache port-side, grep the binary's reset for its
+    analog before assuming none exists.
+(c) **Derived state hides stale backing state.** `currentTemperature` sampled AT the reset read
+    77 (clean) because RTIS wrote it — while the freeze arrived one frame later through
+    `heatEnergy += pendingHeat` from a live producer. Probing the derived cell at the reset
+    instant proves nothing about the producers; trace the WINDOW after, per producer.
+(d) The diagnosis chain that worked, for reuse: roster-wide state snapshot (at-death / at-reset /
+    post-reset) → eliminate conduction by trapping flows with full operands → trap the remaining
+    producer's deposits with operands → cross-reference the operand SHAPE (pure local −z,
+    magnitude = distance/dt, echo at ring-length) against the writers. Each trap eliminated a
+    theory the previous data had made plausible; three plausible theories died on operands.