600 - 1000 rounds a week is a lot. I'd say you have brought muscle memory to a whole 'nother level.

I point shoot at five and seven yards. Mebbe every two weeks, about 100 rounds. Sometimes though I have gone a couple of months without shooting, and I can tell when I return to the range.

After the serious stuff it's time for the .22's for bullseye and targets. I could train more, and perhaps take some classes, but I don't. Basic cost/benefit analysis. If others train more often and receive professional training good for them. Some also enjoy the defensive aspects of handguns, so for them formal training is also very enjoyable.

I wouldn't worry about it.

(By the way, if you are shooting that much, you might want to get you lead levels checked during your next physical...and make sure your range is properly ventilated so you're not ever standing in a cloud of smoke that includes vaporized lead particles).