Coleman couldn't make a layup for years. Mike Gbinije allegedly couldn't dribble as a sophomore. The coaching staff worked with them to improve on those things; that's what they're there for: player development. Roberson was let down by the staff.
What?!? So, based upon this statement, you are saying that any player who did not improve dramatically while at SU, was let down by the coaching staff. This is patently false, as your equation completely discounts the amount of effort put in by the player. It doesn't matter how hard a coach tries to teach a player, if the player doesn't put in the time or effort, or listen to the staff, then it is on the player for why improvement did not occur.
I was a big fan of Roberson, and I always rooted for him to finally have it click. Unfortunately for him, it never did while at SU. I hope it does in time for him to reach his dreams. IMO, the biggest issue, was that Roberson saw himself as a different type of player than JB saw him. He wanted to be a 3 with an outside/in game. That is what he saw himself as, and that is what he spent his 4 years at SU trying to be.
The problem with that, is that his skills did not show that he had that capability to a level that provided JB with any confidence of him doing it in a game. JB saw what he was capable of doing, and wanted him to concentrate on improving those skills. I'm not convinced that Roberson ever put enough effort (in JB's view) on improving the skills JB wanted him to improve. Hence the reason for being in the doghouse.
Unless you have played organized sports at a high enough level, it may be difficult to understand, but the worst thing you can do as a player, is NOT work on improving the skills your coach wants you to work on. This will guarantee a strained relationship between the player and the coach. Just do what he says, and things will work out. You think you have other skills? Work on them on your own time, and eventually you may be good enough to prove your worth with those skills.
Roberson was never able to prove to JB that he had the skills necessary to be the player that Roberson wanted to be. And honestly, despite being a big fan of his, he never proved to me that he was capable of it either.
Having said that, his development of certain players has left much to be desired. Once a player is in his dog house he seems to remain there. When he constantly inserts a player into the game and they make one mistake, the player is immediately pulled; that kills the player's growth.
This is not always true. Both early Dnic & Rak are examples of players who were in the dog house & worked their way out of it. It does happen, and it usually does, when the player finally admits that JB knows what he is talking about, and does as suggested. Both had confidence issues, both figured it out. Roberson had confidence issues, and never figured it out.
Now, this is not just one big rant that JB is always right, blah, blah, blah. I do disagree with some things he says and does. If he has an issue with how a player played, that should stay between him and the player. It should not be aired out in the media. However, when it comes to recognizing basketball talent, and how a players current skills can be best utilized to help the team, there are few better than JB, and none of the people who may be better waste their time writing on sports forums.