The fact that a Tennessee fan would post what the OP did is hilariously ironic. Johnny Majors redshirted Chuck Webb in 1988, then didn't start him until Reggie Cobb got kicked off the team. So we really only got a few games out of him when he should have started from the day he stepped on campus til the day he stepped off. The Fulmer/Cutcliffe/Jamal Lewis fiasco is legendary. Refused to start him until we'd lost the Florida game, even though he was 100x better than Mark Levine. This is an actual quote from Jamal. "Coach (David) Cutcliffe approached me about two weeks before my first start and said `You know, Jamal, you'll never play for me,'" Lewis recalled of the conversation with the Vols' then-offensive coordinator. "I asked why and he said `You're not a good practice player.' I told him that I was a gamer; I get in the game and make things happen." Of course a week after blowing it vs UF again, Jamal rushed for 232 vs Ole Miss when he finally got to start. Proving that he was as he said, a gamer.
There are tons of examples of coaches for inexplicable reasons (usually practice related) playing less talented players and looking stupid when the back up finally gets to play and dominates.