I wouldn't be surprised if most cappers, even the outstanding ones like most in this thread, have a significantly lower win percentage if you compare records before and after the start of conference play. I experience the same thing every year and also see that trend for those who post their picks and their record.
The good thing is tournament capping reflects the neutral site non-conference games so you don't have to consider all of the history, coaching nuances, and teams being up or down based on a previous game be it this year or two years ago.