That Cardinals team went 9-7 with some seriously bad losses over the course of the season. It's only retroactively that you consider them as good as anyone in the NFC, and that's only because they flukily won the NFC tournament. They weren't the "best" team (in the sense you mean it, by some criterion other than results) in the NFC that year any more than NC State was the best team in 1983 or Villanova was the best team in 1985, or that George Mason was one of the four best teams in 2006. I could just as easily point at last three examples and say that I can't stand a sport in which such obviously undeserving teams have a chance to get so deep in its championship tournament.
And if that hockey team was so awful, how'd they go 4-0-1 in the qualifying round? How'd they beat Finland in the gold medal game? That gold medal was more than just a one-game fluke. Brooks knew he had a bunch of lunch-pail guys, so he played an ugly, grind-it-out style of hockey designed to do the football equivalent of shortening the game and running the clock -- basically the equivalent of the service academies running the triple option to minimize their talent gap. They didn't just beat one team more talented to win the gold; they beat several. And while yes, there was a lot of luck involved in the win over the Soviets, it wasn't just that. The Soviets didn't take the Americans seriously, barely practicing beforehand. The coach inexplicably yanked Tretiak (only the greatest goalie who ever lived) after he gave up a second goal. And the Soviets panicked once they were down. When I finally saw a replay of the game a few years ago, the thing that struck me was how the Soviets had no idea what to do once they were losing. They completely lost their shiat and abandoned their normal style; they didn't even know how to pull their goaltender in the final few minutes, for crying out loud. Preparation, playing as a team, knowing how to handle yourself under adversity -- all of these things are important in team sports, just like talent. Yes, that was a hugely lucky game, but the way that both the Americans and Soviets approached and played that game stacked the deck so that a lucky outcome was more likely.