Todd4State said:
Just because one random player almost ten years ago just about every player at every school who was promised a starting job didn't work out, it doesn't mean we shouldn't never, ever do it again.
You should never promise a guy a starting spot at a big position like QB, RB, etc. Kickers, sure, what the heck.
When you promise a guy the job, he's apt to lack motivation leading up to spring/fall (whichever is the arrival semseter) and then underperform to the point where he really shouldn't win the job. The other guys on the team see this, it creates discontent, and it's all down hill from there.
Now, there are ways to accomplish the same goal with a recruit without ever having to promise him anything. You tell him that he'll have to earn it, but you know that he's a very talented guy. You tell the guy you know he's got experience/charisma/whatever and that hard work get him where he wants to go. Tickle his ears a little bit about himself, basically saying that if he takes care of business you have faith that he CAN win the job, but you never actually say the job is his. This covers you in the event that the player isn't all he's cracked up to be and you have to go another direction.