The Vikings validated some of the concerns people had about their legitimacy on Sunday. Things change quickly in the NFL. Last week was about the Vikings proving themselves as a legitimate Super Bowl contender. To come back the way they did, on the road, against an elite Bills team, was incredibly impressive. Even with their seven straight wins all coming by one score, it was much harder for people to question if the 8-1 Vikings were “for real” after that win in Orchard Park. Those questions are back and louder than ever this week. The Vikings returned to Minnesota and…