KSU had the worst scoring offense in the big 12, until Saturday. Granted I don’t expect OSU to fair any better next week vs Baylor.You'd probably have to ask the announcers, since they are the ones that used that term. But OU's defense had looked pretty good in the first three games. So that's probably why.
Martinez is a good player, and if I remember right gave OU trouble last year with Nebraska. Vaughn is a small but tough runner, reminds me of Quentin Griffin but maybe #22 has a little to do with that. OU had no answer for the run game, maybe the defensive game plan assumed KSU would try to pass more?
But you're right... OU did not play up to their potential, and KSU played their best game by far. Maybe they underestimated Martinez? Who knows?
FWIW, OU typically has one or two games a year where the defense just collectively loses their mind. I was hoping a whole new coaching staff would not adopt that tradition, but that's kind of what yesterday looked like.