Good quarterbacks make big plays. A few big plays in close games would make a big difference.
Tennessee is 3rd in the SEC in 3rd down conversions. However, they are 10th in red zone offense, 12th in the SEC in turnover margin, 10th in scoring offense, 9th in pass offense, and 11th in passing efficiency.
An efficient quarterback would have scored on the deep patterns that were open against Florida. Tennessee would have won that game.
Take away the interception in the 1st half against Georgia, right after overthrowing a wide open receiver in the end zone and the Vols lead going into the 4th quarter. Quarterback would have made a big difference in that game, but it could still go both ways.
Tennessee would definately have beaten Alabama, South Carolina, and Vanderbilt with a decent performance from the quarterback position.
Turnovers from the quarterback position were huge in the Notre Dame loss. However, the special teams mistakes might have been too much to overcome.
At worst, the Vols would be 8-2 with better quarterback play.