Visual Verify

Motion pieces: judge from ordered stills, not a recording

Don't record video to judge a movie; capture 6–8 stills at fixed film-clock times (read the scene's data-film-time, not wall time) and tile them with ffmpeg concat listing files explicitly. A glob sorts t12 before t1_2 and the critique reads the timeline backwards.
For beat-synced effects, multiply every effect by a hit envelope (pow(1-phase, 4)) so frames between beats are clean; sustained shear/split/feedback reads as mush, not rhythm. Gate the whole pass with an intensity curve that is 0 at the opener and 0 at the landing.

Never report a visual, layout, or theme change as done based on the diff or a passing test. Look at the running surface.