It’s a tough call. I think any coach and athletic administration would seriously investigate the actual facts related to past transgressions of a player like DGB.
I do not think that Coach Stoops would have given DGB a second chance to become a Sooner if it had not been for the relationship that had already been established with the player and his family during the recruiting process when DGB was in high school. As MsProudSooner stated, every situation is unique. The established relationship between OU coaches and DGB is a significant factor in this situation, in my opinion. Apparently, the OU coaches personally like the young man.
I also think many coaches have the heart of a teacher, and they get special satisfaction when they can contribute to the “salvation” of a wayward young person. Of course, a very significant factor is that DGB has the athletic talent to be an All-American and a success in the NFL. Thus, you have multiple motivations for the teacher/coach to accept DGB.
In addition, I think there is limited risk here to OU, as I think DGB will be gone if he screws up even once at OU. I would not be surprised it DGB gets a drug test every week, and that he and his family agreed to this.
If Coach Coale was given this same exact set of circumstances, I speculate that she would do the same thing, even if she thought the stories were true. But who really knows?
No doubt Sherri continues to learn more about her profession with each passing year, and she certainly observes what works (and does not work) for other successful coaches.