For the most part, teams that win the Super Bowl are fundamentally sound. Players do their jobs, and they do it well. This can be as simple as wrapping up tackles, shedding blocks with perfect technique, or precisely following your blockers. Teams such as the New England Patriots, Denver Broncos, San Francisco 49ers, and the Seattle Seahawks do this better than anyone else, and that's why they're at the top of the league. They execute the fundamentals flawlessly.
This is especially necessary if you don't have a game-breaking talent. If you have a Calvin Johnson or someone similar that can open a game wide open, you can get away with being less technically perfect. However, the New York Jets do not have such a talent. Instead, on a team filled with mediocrity, they must be no less than perfect. It seems since 2009 and 2010 that there have been more missed tackles, blocks, and overall, poor decisions by the players on the team. Some of that has to do with less talent. But even a guy like Jim Leonhard, who wasn't very athletic, rarely missed a tackle or made an error. Even with little talent, you can execute the fundamentals.
This is one of the aspects of the game I would like to see the team focus on next year. A back to basics, if you will. I think we might see vast improvement if they stop making the small self-inflicted cuts and nicks that compile and accumulate into death by a thousand paper cuts. The process started last year with a superior run defense, but too often are there still missed tackles in the secondary and missed blocks by the offensive line. The team can do better with the talent it currently has, but they need to start small and work their way up from there.