Inverting cymbals actually does do a lot of damage, even if you don't see it out right or in plain sight. It makes the plates a lot weaker, and they become much more susceptible to cracking/perma-inverting (When they just won't devert back into a normal position).

That's true, it can leave marks too but I meant they could still be played after the occurrence.

We've still been able to.

Our cymbal players have inverted cymbals many-a-time. Especially when we had cheap ZXT's, they inverted about once a day in the sun. But yeah, don't invert the cymbals, we had a ZXT crack after inverting a few times. Now we have really nice cymbals, but one kid managed to invert one, because he's a moron.

I'm also not sure about it, but it seems like they invert easier when it's hot out. Is this true?

Actually . . . Come to think of it, one day during rehearsal, one of the plate kids inverted their cymbal over 4 times in a 2 hour rehearsal block under direct sunlight (Hot day, too.). But, when we went inside, I believe they only inverted twice.

(Not to mention the extremely bruised knee that resulted in trying to de-invert the cymbal. They were the Zildjian equivalent to B8 Pro's.)