North Carolina's Sean May dunks the ball during the Heels' 92-65 win over Iowa State on Sunday. Streeter Lecka/Getty Images

Amazing, isn't it, how four days of NCAA tournament games can shatter four months of regular-season perceptions?

West Virginia, tied for seventh in the Big East this season, will play in the Sweet 16, while the league's top three teams -- Boston College, Connecticut and Syracuse -- will not.

The Big 12's regular season co-champions, Kansas and Oklahoma, have been sent packing for the summer, while its fourth-place team, Texas Tech, is favored to reach the Elite Eight.

Wake Forest, which went 13-3 in the ACC, has bowed out. N.C. State, 7-9 in the same conference advanced.

The overrated Big Ten has as many teams in the Sweet 16 (three) as the ACC. The supposedly underrated SEC has as many as the Horizon League (one).

It's entirely understandable to find yourself scratching your head and asking the question: Why did we even bother with the regular season when it taught us so little?

If you do, just remember that in spite of such madness, the single most commonly held belief of 2004-05 has yet to be affected. All season long, North Carolina and Illinois have been considered the teams to beat, and four days of tournament action have done little to change that.

Sure, you can argue the pair has yet to be properly tested, but all the Tar Heels and Illini did the first weekend was take care of business, which is more than you can say of one-time title aspirants Kansas, Wake Forest, UConn and Syracuse. In fact, while fellow top-seed Duke had to scratch and claw against a 16-seed (Delaware State) and a nine-seed (Mississippi State), the Tar Heels dropped the hammer against the same level of opposition (No. 16 Oakland and No. 9 Iowa State). And while BC and Syracuse had no answer for mid-major stars Ed McCants (Wisconsin-Milwaukee) and Taylor Coppenrath (Vermont), the Illini seemed to take it as a personal mission to humble similarly touted Nick Fazekas of Nevada.

For all the craziness of the first two rounds (only half of the No. 1 through 4 seeds survived, tied for second-lowest total since 1985), the big picture hasn't really changed. Truth is, it usually doesn't.

I've always contended the NCAA tournament is really two events. There's the first weekend, which is all about weeding out the pretenders, and there's the rest of the dance, where the remaining, legitimate contenders pursue an actual title.