I would like to see a Hall of Adept and Masters

[thegreatonemal]

Here is the problem you can teach a player how to play their role. But you can't force them to play properly after you teach them, brining you back to the original problem of getting them playing correctly. WoW's proving grounds showed this pretty clearly, players would go in play well enough to beat it then go right back to playing like trash.

You can if you've taught the players the proper way to play then you can raise the bar for clearing content. Making the way for harder and harder content as players level up. Players then have the choice to stop playing or play the the standard.