Yeah, it apparently damages the weatherstripping (and maybe the window and other things) and is meant to be used only in an emergency /facepalm. Which is probably why your friend was alarmed.

I didn't care, I still tested it out the day I picked up mine to see where the manual handle is and make sure it works, because just a couple days earlier two people had gotten trapped in a burning Tesla, were unable to figure out the mechanism, and died.