The diagnostic-first capture revealed the failure mode the plan's
four-branch decision tree (A/B/C/D) did not anticipate. AdjustOffset
is CORRECT: 145/146 calls use the into-plane branch, mean zGain
+0.045 m per call, sphere world Z climbs 90.95 -> 92.80 monotonically.
The climb caps at world Z 92.80 (cottage floor at 94.00 is still
1.20 m above). At the cap, the per-step CP reset at TransitionTypes.cs
723-725 clears ContactPlaneValid as designed; TransitionalInsert
should re-establish CP at the proposed position. Step-up logic fires
because the offset has +Z; step-up calls DoStepDown(stepDownHeight=
0.6, runPlacement=true). The downward probe finds NO walkable surface
within 0.6 m below the proposed position (cottage floor is ABOVE,
not below) -- 101 stepdown-reject hits in this capture vs 1 acceptance.
Conclusion: Target E (new). Three candidate fix shapes named in the
findings note. Each one researched against retail named-decomp before
any code lands. Test baseline 1167 + 8 maintained.
Findings: docs/research/2026-05-23-a6-stepwalkadjust-findings.md
Capture: docs/research/2026-05-23-a6-captures/stepwalkadjust/acdream.log
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>