The SEC had 3 bids in this year's Tourney - Florida and Kentucky were in the Final Four, Tennessee made the Sweet 16. That's a pretty good ratio. If you are looking for a reason why SEC teams over-performed, look at the front-lines.
Going into next season, all these guys are 6'8-7'0 and have a chance to be NBA players:
Bobby Portis (Arkansas), Jarnell Stokes (Tennessee), Johnny O'Bryant III, Jarrell Martin and Jordan Mickey (LSU), Chris Walker (Florida), Karl Towns, Dakari Johnson, Trey Lyles, Alex Poythress, Marcus Lee (Kentucky).
There might be more NBA big men in the SEC than in the rest of the country combined. It's just like in football - the SEC has the best athletes. If you are playing PF in the SEC, you are playing some monsters upfront. You are basically going through an NBA season.
Portis, Martin, Mickey, Walker and the Kentucky guys could all be Top 20 picks. If you are a big man in this conference, you are looking at the rest of the country like they are a bunch of little kids. Don't let an SEC team like Tennessee play a team from the A-10 (UMass) or a Cinderella team like Mercer. They just brutalized those teams upfront.
It doesn't matter what the rankings are. If you are bigger and just as fast as the guys you are going up against, you aren't going to be intimidated. If you are bigger and faster than them, you are feeling pretty confident.
You couldn't watch Tennessee vs. UMass and think Tennessee should have been the lower seed. There was just no way - UMass was in a fight for their lives and they were the higher seed.
Florida and Kentucky are the only two teams that consistently make the Tourney and they do pretty well. It's just like in football - the teams with the biggest and most athletic guys have a huge advantage.