Sorry it took me awhile to respond. Long work hours today and yesterday.
I think that's a good question. Hard to say...perhaps. The only caveat I'll mention is that offense and defense are different animals. I think most would agree that defense comparatively is more about effort and determination, so probably is more susceptible to effort lapses.
If we are talking about games that are essentially decided due to a lopsided score, it is quite conceivable that a team would get "sloppy" with the ball on offense, i.e., getting cute with low percentage passes, trying to make moves with the ball they wouldn't normally attempt, etc., etc. Those kinds of undisciplined plays definitely occur in those situations, so the turnovers go up and the offensive efficiency goes down.
I was guilty of that myself. I remember attempting dumb passes knowing that the game already was decided and basically laughing off the turnover (It didn't matter, so who cares kind of attitude...), and I'm assuming that many of us who played basketball were in similar situations. Also, the backups end up playing more minutes in those games, so the talent level drops off as well, further altering results.
Again, just to clarify, I'm not making a case regarding Iowa's offense specifically. I'm simply pointing out that teams with big leads, that basically know they are going to win, will play differently as a result. That, and the increased backup minutes, can and will have an effect on the opponent's statistical results. We can agree to disagree, but to me that's common sense.