snap_to_plane @0x00509c50 semantics extracted at scoping: XY preserved,
Z re-solved so the offset lies in the plane, no-op under the 0.0002
|N.z| epsilon — versus our orthogonal projection, which is exactly the
cos-squared downhill shortfall AD-65 recorded. Branch polarity pinned
from the test ah,0x41 idiom at 0x0050a4fa: into-plane subtracts,
away-from-plane snaps.
AD-66's port carries a mandatory regression scenario: the original
substitution was empirically motivated (uphill contact-flap), so the
contract requires that exact scenario as a test and a full STOP if the
faithful port genuinely reds it — re-filing the divergence as deliberate
is the session lead's call, not the implementer's tune.
Priority note: S4 jumps ahead of S1B in the overnight queue on felt
value — 25-50% downhill XY shortfall is daily-feel, while S1B's
over-inclusion is zero-felt fidelity. The campaign's
membership-before-query ordering is about masking, and an over-inclusive
residual masks nothing downstream.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
