4 wins isn't acceptable, but that's the point where you really have to look at the team and how they played in those games. They have 8 games on the schedule where losing them wouldn't be a shame, but if they don't play well and lose, like they did on occasions last season, then 4 wins will have him gone. We can't have anymore 38-7 to OSU, or 20-0 to PSU, or 12-0 to Iowa. To have a 4-8 season and survive, Brewster is gonna have to lose a ton of nail biters and to the toughest teams. Say in theory, we beat MTSU, NIU, So Dak, and Illinois. We lose the rest of our games. But if we have games like 21-20 to USC, 27-24 to OSU, 20-17 to PSU, etc., and it's just a matter of bad fortunes or just being on the cusp, but not quite getting there, then I could easily see Brewster being retained because we won't lose a ton of players the following season.
On the flip side, say we get an extra win, 5 wins, but we also have 38-7, 20-0 type games again. Brewster will likely be gone at that point. No bowl game plus the offense still sucks = firing IMO. To be honest, that's my main evaluating point this season, how does the offense improve, cause that group is experienced, they have been together for a little bit, albeit a new system, but still have played together for a while. If they can't get much better this year, then that will be an issue for me.