Yeah i dont know the mechanical specifics of how quick it will wear out a clutch, it seems to be controversial subject. I have well over 20,000 miles on my bike, clutching all day every day since day one, and just now its starting to slip a little. Its nothing i worry about in my opinion. my chain and sprockets lasted about 20k as well before i geared up , if your going to stunt, these should be the least of your worries since you need to do it thousands of times to mess them up, but one mess up while stunting can demo the bike... If your not willing to wreck youre bike at any given moment, dont stunt.