Tyler's on-device verdict at 3d1e91ea: better but not perfect. This probe
actuates the shape of his input — small (12px) wheel deltas at slow (~32ms)
cadence, no settling — and samples the tracked reading row's rect.top,
scrollTop and mounted count EVERY rAF, so one-frame events are visible.
Flags frames whose rowMove escapes the slow-wheel staircase envelope
(reversal <= -3px, or shove >= 2*delta+3px), pairs escapes that cancel
within 3 frames (one-frame flash of a deferred correction) vs unpaired
(felt lurch), pure rect.top in the flag condition per the W4 framing.
At tip b170680d (includes W1r3 fe786ea4): Chromium 0 escapes / 3447 frames;
WebKit 81 escapes / 1754 frames — 11 flash pairs (-27.5 shove then +28
correction one frame later) + 59 unpaired single-frame jumps of exactly
35px / 41px recurring every ~6 rows. Diagnostic, non-gating.
Co-authored-by: Tyler Longwell <tlongwell@block.xyz>
Signed-off-by: Tyler Longwell <tlongwell@block.xyz>
