Call me old fashioned, but I find it more usefull learning how to punch an oponent till they
bleed, than punching a tree till I
Do what you want, but tough bloody knuckles wont stop you crying like a baby when you get your nose broken, and that is a possibility seeing as how you have gone on record as saying that you only do light contact sparring in your school.
Chris Leben put his fist through a door on 'Ultimate fighter', it messed his knuckles up real good. Strangely, he got his a$$ kicked when fighting a human oponent.
Make of this what you will, and find a good arthritis specialist in preparation for your future tough guy