This week will be a good test for Thomas Brown. I think the Vikings, more so than any other team, is incredibly dependent on good preparation and game planning from the OC. It's not happenstance that the teams that have put up points on them this season were led by McVay, Johnson, and LaFleur.
If they can do that, the Vikings aren't unbeatable. If they can't, and it's not easy, it will be a third straight loss on Soldier Field, and presumably be 6 straight losses when they get murdered by the Lions on Thanksgiving.