I wouldn't say this was necessarily a regression. This is basically what has happened to us in nine of the last eleven seasons.
These are our seeds in the NCAA Tournament the last eleven years:
2002 1
2003 3
2004 1
2005 1
2006 1
2007 6
2008 2
2009 2
2010 1
2011 1
2012 2
In that time we have made it past the sweet sixteen exactly two times. That means that, based on our seeding, we have badly underperformed in eight of the last eleven tournaments.
It has been incredibly frustrating for the last decade plus to be knocked out of the tournament almost every year long before a handful of teams that we beat during the regular season were. What we have been doing for the last decade plus just does not win championships. We are year and and year out one of the most consistent and competitive programs in the NCAA all season long and through the ACC Tournament only to fall flat on our faces come NCAA Tournament time.
Almost every year it seems like we can vastly outplay top teams from November to February and then we collapse. My personal theory is that it has been years since we had a legitimate bruiser of a big man on the inside. For years we had guys like Boozer, Brand, and Sheldon and they allowed us to spread the court and shoot threes because they could single handedly battle for boards and get us second chances. In my opinion, Brian Zoubek's emergence as a dominant Center is what won us the title in 2010. I don't know, I just think that Coach K is always able to get his teams to overachieve during the regular season but come tournament time they just are not set up for success. You cannot argue that our performances over the last decade in the Tourney have been pretty pathetic compared to the way we have played in the regular season.