It is your OPINION that this stat shows that Iowa could take a lot more chances. As another poster pointed out, being aggressive or conservative doesn't = turnovers. Making a bad play, a bad read, running the wrong route, not holding onto the ball and fumbling = turnovers. You could run WR reverses all game long, why would they = more turnovers? You could run the ball 40 times playing conservative, and the RB could fumble 4 times (See Nebraska VS ISU when they turned it over 9 time, it wasn't because of "aggressive play calling). I bet you can't find a statistical correlation relating more aggressive play calling = more turnovers.
KF doesn't run a conservative offense to limit TO. KF runs a conservative offense to take advantage of usually superior defenses that he has. What kind of idiot wouldn't play to his teams strengths? Why come out in a spread O when your offense is very average, and your D is very good?
I know you like to give credit to Norm, for past success. Yet good coaches use what they have. Rich Rod was an idiot, and tried to make over an entire program to his gimmick offense, and it was a complete failure. There is a fine line between success and failure at this level. Rich Rod didn't fail because he was a bad offensive football mind, he failed because he tried to take a square peg and shove it in a round hole. That is exactly what would have happened to KF if he would have been running some high octane offenses when he defenses were awesome under Norm.