Enlightening interview. I know deciphering Mangini is not easy, but the way I read it is, he pretty much knows his role in Dream Theater is just to lay down creative drum parts, not really pushing songwriting or direction of the songs. I guess after MP split, John wasn't going to give that up to anyone else (except for JR, of course).
Sounds like Mangini does have a lot more to offer, however. Interested in his solo work, whenever it pops up.