How It Happens: Pretty easy to see. The seven remaining teams without a loss -- Southern California, Oklahoma, Auburn, Miami, Wisconsin, Utah and Boise State -- come from seven different conferences, and none of them play each other the rest of the way. Just win, baby. Sure, Miami could lose to Virginia, USC to UCLA or Notre Dame, Wisconsin to Iowa, Auburn or Oklahoma in their conference championship games, etc. But a world exists in which all -- or six, or five, or four -- of those teams finish unbeaten.
Ramifications: Doesn't BCS stand for "Bowl Chaos Series" anyway? Perhaps it should, because that's what would result -- again. Yes, the BCS standings could change in the next month and a half. But for these purposes, say things remain how they are now -- with USC first and Miami second. Oklahoma -- which would have victories over Texas, Oklahoma State, Texas A&M and perhaps Missouri or Nebraska in the Big 12 title game -- would be livid. And what about Auburn, playing in the brutal SEC? Ditto.
This scenario would also have an impact further down in the BCS games. Take Utah. If the Utes keep winning -- particularly if they do so convincingly -- they likely will not fall in the writers' or coaches' polls. But they aren't guaranteed a spot in the BCS unless they finish in the top six. Currently seventh, their remaining schedule -- five teams with a combined record of 13-19, with only Wyoming above .500 -- likely won't put them any higher. Boise State, 14th in the BCS standings, has almost no chance of receiving a berth. A team not affiliated with the BCS conferences must finish in the top 12 to even be considered, and the Broncos' remaining schedule -- all teams within a game of .500 -- doesn't offer the chance for an eye-popping win. So there's a very real chance that both the Utes and Broncos will be left out, but a team from the watered-down Big East is guaranteed a spot. West Virginia is the top Big East team in the BCS standings -- and the Mountaineers are 20th.