Per-round bisect of a176d07..3202193 (56 builds; timings inflated by concurrent UE builds) plus a clean quiet-machine endpoint re-measure: L14 12.62 vs L61 14.65 worker-s (+16%), LOD0 3.99 vs 4.99 ms/tile. The owner's Windows x2 is therefore mostly on the Unreal side or not like-for-like. Four-strate U2 plan: all strates generate and are deterministic; passage 0-1 lower mouth is out of FI's band, 0/3 interfaces pass, FI/TN/VS use legacy evaluators. R33: ranked Unreal-side suspects and Windows experiments. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_016dhxM43dnWvUu2B5Ph1iG1