Dude, it was obviously a hyperlative example to make a clear point. It had nothing to do with relative skill/success as a coach (BB to Ollie). It applies to any and all good coaches.
Look at Duke's staff. For a long time it has been pretty much all guards. Plus K. Scheyer. Capel. Nolan Smith. And Nate James, who did play some small forward. Formerly Wojo, Quin Snyder, Amaker, Collins, etc. All guards.
They do pretty well.
There's a reason guards often make good coaches. It's because they are the communicators/orchestrators of the team. The proverbial coach on the floor.
Some times you have to admit that the raw ingredients aren't the best. Brimah/Nolan weren't gonna develop much anywhere. Facey maybe could have come along faster somewhere else, maybe not.
Enoch and Durham didn't finish, so you can't say anything about their future development vis a vis UConn. You develop as a player in practice and the offseason. Then show off that development in games. Yes, experience is important, but if you aren't developing off the court, you don't deserve to be on it. Enoch didn't get much of a chance for that reason. He was very raw coming in (and reportedly wasn't much on D), so it's not much of a surprise he didn't make the jump yet. Still a chance he might.
And as you say, Durham, hobbling around, didn't get opportunities. I don't think anybody expected him to this year.
Ollie's biggest failure was not landing better players. He targeted them, but failed to land them.