Yeah I find that when I try Ctrl Z, it doesn't register the Ctrl the first time. I usually get it to work on the second try, only remember it taking three tries once. I also notice it with Ctrl M. The few other shortcuts I use, like Ctrl A, Ctrl H, and U...they all work fine whenever I attempt them.
This is one of the main reasons I've really slowed down mapping recently, it's so frustrating when you're trying to detail a building, and in order to copy and paste anything you have to hammer Ctrl+C god knows how many times until it actually copies.
Anyone else get that thing where if you paste something and it turns out to be the wrong thing, you press Ctrl+Z to undo but Hammer freezes for a few seconds?
Gets on my tits. Not that I have any....But if I did it would be climbing all over them.