The drop between 4 and 5 in the Big East has been widely repeated (including by me at some point, I'm sure), but it is kind of a myth. Haslametrics, which puts more weight on the more recent games (in other words, relative to Kenpom, it discounts the November games and the pre-season rankings), currently has Xavier ranked 25th overall and 349th in momentum, while Marquette is 26th and 18th in momentum. Butler is 28th and 141st in momentum. The gap between 2-4 and 5/6 feels bigger than it really is because Seton Hall and Creighton have generally played well lately; Xavier is still highly regarded in the polls because they've got a great record and can play some great offense, but their true value simply isn't as high as their perceived value. The gap is basically nonexistent (right now).