This happens somewhat frequently in smaller conferences---it's far less common in the bigger conferences for reasons that should be obvious. Interestingly, Lon Kruger's 1999 Illinois team very nearly pulled it off. They were 3-13 in conference play, went in as the 11th (last) seed, and made it all the way to the finals of the Big 10 before falling to #1 seed Michigan State.
There have been a hand full of other teams in recent history that have nearly made it through a major conference tournament with records similar to OU's (2008 Illinois, 1997 Mizzou, 2007 NC State, etc.), but the only one that's really pulled it off was Georgia in 2008. They were pretty awful and wound up winning the SEC tournament. I'm sure there are other examples I've missed, but suffice to say that it is not a common feat in power conferences, and I'm not going to hold my breath for OU to pull it off this season.