Blast! With only a half-hour left to go, after doing noise removal and normalization, the audio is still too low quality to edit. This is probably due to the fact that I was trying a new configuration for the recording apparatus, which put the microphone slightly further from my head, and has apparently altered the audio enough to make it untenable.
As a professional, I know I have to scrap it and start over. I’ve had to do it in the past, but it’s never fun. Worse still today, because I’ve put so much work into getting the whole thing done in just four hours.