Stryker's diff-scoped run against this cut reported CultGeometrySurfaceNets
.Extract's `if (inside == (OrientationSign[axis] < 0))` - the sole authority
for quad winding after F4's fix deleted the geometric cross-product fallback
- as a Survived Equality mutation (== -> !=). Hand-mutating it and running
dotnet test directly failed 4 of 38 SurfaceNetsTests (the three per-axis
corner-order tests and the outward-winding test), confirming it is a real
vstest coverage-based test-selection miss, not a genuine gap. Recorded this
as a second confirmed case alongside the mtp/static-readonly-initializer
caveat, per this cut's verification requirement to hand-confirm any survivor
that looks like it must be covered.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>