the trick to doing it, and getting away with it, is to wait until you have a busted stick - or keep one in your bag that you can pull out when you need it.. take the busted stick and clobber somebody square in the head with it.. when they turn around with that WTF look on their face, you show 'em the other half of the busted stick and shrug..
I was onto that scam for a loooong time, but still kept getting hit with stick fragments.. Occasionally it happens, for real, but most of the time its a cold blooded scheme to give me a concussion...
Friendship is like peeing your pants.. Everybody can see it, but only you can feel the warmth..