listen to the man, it can hardly hurt. however i would like to confirm, the reason you havent had your nose broken is either because the people hitting it dont punch hard/accurately enough, or your a lucky bastard.
i have had my nose broken, so i know about this shit.

also your eyes watering is natural, you are applying a direct shock to a bone linked closely to your sinuses.
you force the bone inoto the skull, vibrating around your tear ducts which sets them off.
i can imagine training your cartalige could act as a shock absorber...