I don't think the play calling was all that bad, it's just that our defense isn't really where it needs to be. We out yarded them and you take a play here or there, and have it just execute, then we escape with a win.
The key was that Iowa State, and for that matter, all the teams that have beaten us, have made adjustments to our defense because it over pursues. The backward screens, the QB runs, etc, to areas where players are vacating spaces for pursuit allowed Iowa state to move the ball and score.
You take out the interception for TD, add Johnson's TD (that was incorrectly called out of bounds) and KSU wins this game, if you just don't allow them to do anything else.