His departure doesn't make much sense, under any set of circumstances.
That said, it's got to be one of three things, or a combination of them:
1.) Kaaya was tired of being hit. We had a porous OL, and he was sick of losing molars. The weakest reason to leave, but in being "bred for this," la familia may have coddled him too much.
2.) He doesn't get along with Richt and/or Richt's offensive philosophy. I don't doubt he may have been frustrated by some of Richt's calls, but being that Richt is an approachable "player's coach" with an impressive track record with QBs, I have a hard time envisioning true tension between the two. But who knows? Seriously. Who knows? Because I want to.
3.) Piggybacking on the whole "bred for this" thing...His west coast mentors and family were blowing too much sunshine up his skirt. Telling him he's better than he is. That he's more ready than he is.
I'm supremely disappointed he's not coming back. I think we could have been special next year with him -- might still be! But he had the opportunity to really cement Miami as "back" next year all while improving his draft stock and bottom dollar. I don't at all understand how you leave Miami given those circumstances, and having never beaten FSU. It's one or all of the above.