Just a few quick thoughts I had.
1. I believe full-heartedly that Steve Pedersen thought that his actions were the best direction for the program, but the downfall was his over-confidence in his own genius, and being quick to dismiss any other possible ways of going about things.
2. Say what you want about Callahan, and a lot of it will be fair, but the guy did get us 8 and 9 win seasons, and into the top 15 of the national rankings (Maybe it was #17, can't remember). Not saying he was a good coach, but he wasn't a terrible one. Terrible coaches never make it to bowl games, have consistent losing seasons and don't show any signs of hope (unless you have a ton of talent, then you are still considered a good coach, ie Mack Brown).
3. Maybe Solich can come be AD when Osborne finishes his career