I disagree

Not only did I know this personally, he echoed it in a recent interview when Charlie, Jr was in the news.

It was a very good interview on Sirius College radio.
He was asked about things he would change. At Kansas, nothing... he told them it would take 6 years and he was fired in year 3 at 2-2.

At ND: "That's the biggest regret in my life. I didn't want to go anywhere else. It is my Alma Mater. I love the place. I still have a home there and a charity there and they will stay there and I will live there. My biggest regret is I put guys together on the staff that really didn't know each other well and I didn't manage that well. It's all on me. I learned a lot from that and regret what happened there but at the end of the day, that's on me."