I tried to address those points in my reply to Cliff, but I don't think this year's team was/is objectively different than last year's team in terms of potential. Flores' defense is better, yes, but statistically just middle-of-the-pack league-wise and they've blown multiple chances to win games at the end. To be fair, they've also made plays to win games, but they are far from good enough to believe they could be the difference for the Vikings if they make the playoffs. YMMV on that.
In theory, any team that makes the playoffs could get hot, including the Vikings. But there is a difference between a given team catching lightning in a bottle and riding that wave to a championship and objectively looking at a given team and saying they are in the conversation to legitimately contend for a Superbowl. I've tried to explain why I think that if the Vikings had remained perfectly healthy this year they'd still have fatal flaws that would likely have emerged to sink their chances. With a few key changes this offseason, though, they could potentially overcome them. And as for KOC, he is a young head coach and could still adjust his playcalling to remain more aggressive when his team has the lead. I just don't see these things happening this season, and had Cousins remained healthy and guided the team to another first-round playoff exit, I think there was a good chance we'd see much the same next season as well. At least now they almost have to go in a different direction, and with a little luck and some astute moves on the part of KAM this offseason, the core of a Superbowl contender is there now.