Band 31-40 is the best video result in the sweep and invents unprompted
dialogue on every single run of it — a trade that the bisection proved
cannot be dropped by narrowing, because neither half reproduces either
effect.
H3 packs video, text and audio into ONE sequence, so a plain repeat
doubles the block for the audio rows too. This restores text and audio
rows to their single-pass value after the extra passes, keeping the
repeat for video only.
It does NOT undo audio's influence on the second pass — attention had
already mixed the twice-processed audio rows into the video rows before
they were restored — so it fixes the audio that comes OUT, not the video
path. Whether the video gain survives that is the experiment.
Off by default so the measured sweep stays reproducible, and it falls
back to repeating everything when the mask code meets a shape it has
never seen, rather than silently dropping the feature.