The defense will be good enough to win games against average to below average teams even with a backup QB. If Goff goes down with a season ending injury than perhaps the season is lost. But if he needs to miss 5 or 6 games, a couple of wins could be the difference between making the playoffs or not.

I'd like to see an upgrade over Mannion. But it would be interesting to see him play with some protection and an actual game plan instead of the vanilla preseason stuff.