[Cyril_HN]

I think people forget that the purpose of performance is one of two things:

1. To perform for its own sake.

2. To drill the specific skill of live performance.

If you don't want to do either of those things, it is not an efficient way to improve. You must perform to hone the skill of performance, but you should not perform to practice other skills.

Caveat: sometimes you can't drill multiple skills together and performance is the only context where you can. However, performing with that in mind is very different to performing generally.