Can I ask what this tool does? I was trying to figure it out (the GitHub page isn't terribly clear) and came to the same conclusion you did (delete a chunk of the transcript and the tool would delete that audio).

I think I just lack experience in this area. I've used Audacity to cut out parts of audio / splice together two clips and that's about it, so I clearly don't have enough background to understand what this tool does.

Can someone clarify what this tool does, please? :)

It does exactly what you think it does. You can cut parts of the original file without having to edit the waveform (like you would in Audacity). Instead, select the parts directly just like you would in a text editor.

What it does not do is generate new words (ie you type a sentence and it adds that to your file as voice).