Following some insightful comments by frozenm and others, I've redone the timing in A* Episode 2 to be based around the spoken lines rather than the subtitles; it had been based around the subs because episode 2 was originally done without any sound at all. Anyway I was able to weed out over 90 seconds of slow time (1/10th of a second here, 1/10th of a second there...) and tidy up the lip-syncing, so it's a much snappier viewing experience now. Thanks to those who've left comments, they're helpful!