Checked both. It's not the commit rule. I ran the raw decoder output (no caption pipeline at all) on every scene, and Parakeet-unified scores identically: same WER, same deletions, all 16 scenes.
The deletions don't cluster before pauses either. Over the 6.5 uncut hours, 92% of Parakeet's extra deletions are mid-phrase. What they are is disfluencies: about two-thirds are repeated words and fillers, and most of the rest are false starts. Stuff like "I was [I was] out in", "until we [until we] moved", "[you know]". The references are verbatim, Nemotron keeps the stutters, Parakeet-unified cleans them up.
If you excuse those deletions for both engines, the uncut WER is 10.12 vs 10.19. So the whole gap is transcription style, not accuracy. For live captions I'd call dropping "I was, I was" a feature.