For once, OSU’s defense didn’t hold up its end of the bargain. Texas knocked down a high percentage of its shots, but even when the defense was clicking, it gave the No. 10 Longhorns too many second-chance opportunities. While the Cowboys scored their highest point total in five weeks, the defense gave up a season-high mark in an 89-75 loss in Austin on Tuesday night. “Eighty-nine points, you…