Found while controlling the timing probe before a settle_time run, not by
reasoning about it.
title_timing_probe.py s plate detector thresholds a green-glyph pixel count at
400, and its control checks two committed movie frames that both score 0. A real
boot disagrees: in one 100 s attract window, 17 frames scored at or above 400
and the peak was 5393. The attract movie has green content in the plate region.
The probe is not wrong -- its state machine refuses to look at the glyph until
the content classifier has already labelled the frame title_noplate or
title_plate, so the false positives never reach the drive. But it is safe
because of that gate, not because the threshold discriminates, and the
distinction matters for anyone reusing glyph() on its own.
Recorded with the general form: a two-frame control over a three-and-a-half
minute movie is not a control over that movie.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QsEPXWVaEpyfudtR6re1Pd
6011512334