No, he's not. At least not on the rushing stats.
Iowa's conference ranks in rushing yards and ypc since 2001:
2001-6th and 3rd
2002-2nd and 2nd
2003-5th and 4th
2004-11th and 11th (We all know these numbers suck, and we also know why)
2005-7th and 6th
2006-7th and 4th
2007-10th and 11th (playing with Christensen at QB helps explain this one)
2008-1st and 1st (Greene helps explain this one, but that line was awesome, too)
2009-10th and 9th
2010-8th and 7th
2011-12th and 10th
2012-12th and 10th
2013-5th and tied for 6th
Only in five seasons since the turn of the century has Iowa finished 10th or worse in either of those categories. Sacks also count against a team's rushing numbers. So if you want to argue that Iowa's lines are below average pass blockers more often than not, go ahead (but I'd need to see sack stats to back that up). But we typically have a good line to run behind.
These rankings came from the NCAA.
It's also important to look at who's carrying the ball. In years like 2002-03, 2006 or 2008, we had backs (Russell, Lewis, Sims, Greene) who could hit the homerun once they got into space (hence the good ypc rankings). In years like that, the lower rushing yard numbers are more a result of the number of carries than the OL's effectiveness.
Conversely, I loved Adam Robinson to death when he was in the backfield, but he wasn't a homerun threat. Neither was Coker and neither is Weisman. Which means that even when big holes open up, awesome things don't always happen (Coker was notorious for this). That's going to negatively impact both numbers.