How It Happens: In short, everyone loses. This scenario is somewhat easier to imagine than the above, simply because three teams rarely finish the regular season unbeaten. USC and Miami seem the most likely to remain unbeaten, at least in part because they don't have to play a conference championship game. Ask Oklahoma how difficult -- and surprising -- that can be.
Ramifications: If one team from a BCS conference finishes unbeaten, then the scramble will be for the second spot. But if everyone loses at least once -- well, rewind the tape of last year's howling, hit play, and listen to the squawking. Take the following example: USC, Miami, Oklahoma, Auburn and Wisconsin all lose just once. Would Florida State, which lost to Miami in the season's first week, rise above the Hurricanes in the rankings? What if Auburn lost to Tennessee in the SEC title game? Would the Tigers turn into this year's version of Oklahoma, which last year was crushed by Kansas State in the Big 12 championship game -- yet earned one of the top two spots in the BCS title game anyway?
Should this happen, the upshot would likely be -- drum roll, please -- more tinkering of the BCS formula. "We had hoped that we would arrive at a point in which constant revision of the poll would not be necessary," said Big 12 Commissioner Kevin Weiberg, who chairs the BCS this year. But they're not there yet.