Gotta defend Snyder and Prince. I know both of them. They are not so dumb as to promise an unproven 18 year old a starting job. Like any reasonable recruiter, they told the kid, "If you prove yorself, you can play."
I think if JF was promised the starting job, it would have been his from day one. Everyone "knew" it was neck and neck between him and DM. How easy would it have been for Prince to say, all things being equal, we are going to play for the future? Personally, I think he didn't do it because JF wasn't ready. In fact, had it not been out of necessity, he might even have redshirted him. IMO