For the past few years, Gelf has had the same message for big-conference bubble schools who claim that they should have the right to the last, precious at-large spots over smaller schools: Put up or shut up. That's because, despite all of the hype surrounding them in the weeks leading up to Selection Sunday, lower-seeded at-large teams from the SEC, ACC, Big 10, Big East, Big 12, and PAC 10 almost never do anything once they reach the tournament. Gelf dug deeper into the stats to directly compare the performances of bubble teams from big and little conferences.

In the past 10 years, 46 bubble teams from BCS conferences have entered the tournament at 9-seeds or lower. Only seven of them have advanced to the Sweet Sixteen, and of those, only Missouri, a 12-seed in 2002, advanced to the Elite Eight.

Compare that performance to the 57 non-majors who have also been given relief off of the bubble and into the tournament. Seven of those teams have made it into the Sweet Sixteen, including George Mason, who made it to the Final Four last year.

That means that they perform just about equally. Furthermore bubble teams from all conferences do much worse than the other non-majors inhabiting the same region from 9 to 12, even though nominally they should be about as good: Of all the low seeds in the tournament, smaller schools overall, bubble and non, do about three times as well as big conference schools.

Who are these other 9-12 non-majors? Conference champs. It seems that momentum really does count for something. Teams hot off a conference-tournament victory in the 9-12 seed region are more dangerous opponents than teams lifted off the bubble. This effect isn't as pronounced in the big conferences, at least anecdotally, perhaps because the best teams in the Big 10 and ACC don't need to win their conference titles to make the tournament. But in the Big South and its ilk, don't win your conference tourney and you might not be in. So before March Madness begins, watch those conference tournaments for the hardest fought action—and your best bet for the next Cinderella.