Oregon hired Brady Hoke as DC and he took Michigan to the Sugar Bowl, he was lousy as DC after never having been one in his career.
Another Urban DC, Kyle Whittingham at Utah made Dennis Erickson, an NFL coach and national championship college coach as co-OC. He had been OC way earlier in his career. He was pulled out of that position a year later.
So as far as elder statesmen advisor, I'm fine with him. As far as OC, I'm okay with it but I'm not jumping for joy like many seem to be. He could be good and he might not be, his track record as play caller isn't really one you can see for me to come down on one side definitively.
I also don't see him as analagous to Friedgen. Friedgen was the OC of a national champion GT and OC of the Chargers when they made the Super Bowl. It's very easy for a fan to point out his track record as OC/play caller and see the results. I can't say that about Kill.
Like I was with Mehringer and most things, I'll keep my feet on the ground. Not going to say home run, not going to say he sucks I'll just say I'm okay with him and hope he does well.