Geldings will do that anyway but when they get cut there is a certain thing that is supposed to be done so that they cannot get "it" all the way in the mare but somethimes that isnt done correctly and the gelding can still completely breed the mare. So if he completely bred the mare it means he wasnt fixed properly but that really doesnt affect anything except that. If you dont want him breeding the mare I would just seperate him in a pen a few feet away because if he really wants to breed the mare he might attempt to do so through the fence. xP
