Are you seriously asking if muscle memory is a thing? Because yes, it's absolutely a thing and anyone that's done much with interfaces would know this.
You feel you're not accomplishing anything because of "muscle memory" - this is a great insight - thanks a lot for that. Where did you get this phrase from?
IIRC there is recent research confirming it is at least partially stored in the same are responsible for muscle memory, which supposedly explains quite a few things.
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