I've found myself driven to say that so many times when someone's getting me good, along with related variants (I can't stand it -- Not there -- I'll do anything), and it really kicks up the suffering a notch when you're taken to that extreme, you manage to get those words out amidst your helpless giggles, and then the person tormenting you disregards your plea... it really drives home the fact that you've got no control over this situation, that your words can do nothing for you except possibly goad your tormentor to greater wickedness.