If the Seattle Seahawks had reached the 2011 Super Bowl you'd have been justified in worrying about their win-loss record. But as the 10-6 Green Bay Packers prepare to take on the 12-4 Pittsburgh Steelers the Super Bowl serves less as an indictment of the NFL's playoff system than as an example of the limitations of win-loss records—especially in a 16-game season. The Packers—like the St. Louis Rams—found themselves behind an inferior team in the NFC North, with their point differential telling a story their wins and losses don't divulge.
In 2011 the Packers had the second-best point differential in football, scoring 148 points more than they allowed—five more than the Steelers managed. According to Pro-Football-Reference they both had identical win-loss records of 12.1-3.9.
There are two possible lessons to take from a number like that, and the simpler one is that the Packers got unlucky. Some people will no doubt attribute their poor record in close games to a character flaw, but the fact is that there's just no evidence for such an assertion. If you're looking to give them a demerit re: 2011 Super Bowl performance because of that alleged character flaw—well, there's an Onion article I'd like you to read...
The Seahawks, if you're looking, as a Rams fan, for one last chance to wallow, had an expected win-loss record of 5.5-10.5. Well, at least their draft position is ruined.