<< When I have something I want to freeze, I turn those bars into an 'Artist Performance File.' >>
That's correct.

<< Those bars are then somehow reloaded (I'll search for how) back into the project and can be programmed to play within the chorus as they did before. >>

Yes. I'll be happy to assist you if you need it. There a multiple ways and according to your workflow, we'll get you situated with what fits your workflow or project.

<< Where ever they are, I mute all the same bars with F5 so whatever else would otherwise be playing at the same time in the song file doesn't. >>

Yes

<< In case I changed my mind about the performance file's iteration in the 3rd chorus, I could mute it with the Audio Editor and unmute that chorus in the active song file. (Yes or no?) >>

Yes

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