Definitely, should have mentioned that. However it is interesting that using temperature may lower the quality of the output and you may get a C and not the hoped for A+.

Could you run it once to get the A+ version, then feed it back that version saying "change x% of these words to be unlikely choices in a way that keeps all the meanings of the essay" to avoid letting the low-probability words hamper the main contents, just the way it's described?

As far as I know lower temperature doesn’t necessarily mean higher quality, just more determinism and less creativity so whether that’s desirable depends on what you’re trying to generate

Temperature above 1 often results in nonsense though

I completely hedged that with two "may"s. Agreed re it depends on task at hand.