QB is the most visible on the team. By benching senior Mangum for a frosh, the message would be loud and clear to the rest of the players that nobody's job is safe if they aren't performing.

Aside from that, having a Qb that can move the ball and score can do wonders for the defense. You'll be surprised how they respond to a new kid running the show.

They played winnable D the first 4 games, but that load just got too heavy to bear slogging into games 4 & 5 vs with a 3-and-out O putting them back on the field every few minutes.