S0 wire probe (live capture, retail actor via ACE) refuted the premise
the #39 machinery was built on: walk<->run Shift toggles arrive as
EXPLICIT UMs (0x0005 <-> 0x0007@runRate) because retail's default-
difference packing baselines forward_command against Ready — W-held is
always packed, and ACE re-emits it unconditionally with the holdKey
upgrade (MovementData.cs:104-119). The frequent flags=0 autonomous UMs
are genuine keys-released / heading-only states; retail applies them as
full stops (InterpretedMotionState ctor 0x0051e8d0 defaults Ready +
move_to_interpreted_state 0x005289c0 flat copy).
Retail has NO pace->animation adaptation anywhere in its inbound
pipeline (two decomp dives + ACE cross-check, deviation map DEV-2), and
the refinement layer's 0.2s-grace re-promotion after legitimate Ready
UMs was itself the observed Ready<->Run thrash / rubber-band component.
Deleted: ApplyPlayerLocomotionRefinement, UmGraceSeconds,
PlayerRunPromoteSpeed/PlayerRunDemoteSpeed, RemoteMotion.LastUMTime,
the synth-player refinement call in OnLivePositionUpdated. Player-remote
cycles are now UM-driven only, exactly like retail. NPC PlanFromVelocity
path untouched (S6 unifies).
S0 findings + S1 live validation (0 false UM_STALE drops across 280 UMs)
recorded in docs/research/2026-07-02-inbound-motion-deviation-map.md.
fix#39: closed — root-cause narrative corrected, machinery removed.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>