Depends on whether your original goal is to match individual dogs or if the original goal is to breed good dogs, perpetuating a family/line and matching dogs from there. If all one is doing is trying to win matches then game enough is all one would need, as the individual dog is all that one would be concerned with. Granted, I would end up with a yard full winners, even more in the graveyard, and a very low percentage of successful dogs from these "individuals". But, my original goal of matching winning dogs would be a measured success.
On the other hand if my goal is to produce my own winning dogs then I have to look at everything. First in the individual for gameness, ability, talent, athleticism, mouth, desire, etc..etc.. Then to his littermates. Do they have these same traits? If not, I need to move on. If so, then move to the parents. If the traits are still there then this is a pretty good place to start. Then finding another within his/her family with the same traits (or better) and move forward with the breeding program.
If I were to lay out my goals in the beginning answering the question is rather simple. Sort of a 'short haul and long haul' mentality. EWO