I don't think this can work as such. First of all, a fighter is pretty much a standard build so, if the fight is without weapons, the outcome would be pretty much random. If however weapons and armor are used, then the gang with the better equipment will definitely win. So there is no competition. Unless of course this was to be like a crime, with many more parameters to set (e.g. location, time, position in the room etc) which would give a considerable advantage to the one with the better strategy, or, if there was a new fighting system for that purpose where the fighters would be hand to hand (a boxing match in essence) that would focus a lot on the strategy of the fighter in addition to the skills (e.g. focus defense high or low, focus offense on head body, quick but weaker hits vs slow but stronger and so on) and where non fighting skill would provide an advantage too (e.g. a player with persuasion could intimidate his opponent into striking less often, an organization character could be better in anticipating the opponents moves thus defending more effectively etc). Come to think of it, the second scenario could also be used for gambling like horse races. It could also be a great way for fighting characters to earn respect since they are not so good at robbing people. There could also be a mob along, as a trainer, giving the fighter the bonus of the additional specialty.
Helper... FROM BEYOOOND!!!