*laughs* Yeah, try to take on a cook while they're in the weeds just try it. You will be on the losing end of that one. Though to be fair, if a cook messed up a cuisson that badly, then they are probably getting trout from the sous-chef or chef while making you a new one.
I don't think I ever sent things back. I will just live with the mistake. If you mess up royally enough, I will just pay and not come back.
Working in the restaurant industry you see weird send-backs though. Some customers are just smurfing crazy/stupid. The funniest is when the customer doesn't know their cuissons. "They ordered it medium" "It is a perfect medium" "They want no blood." "So well done?"