Four weeks is a pretty small sample size in an NFL campaign, but here are a few things that have either become obvious to us, or could happen through the last 13 weeks of the 2012 NFL regular season. The Arizona Cardinals are the best team in the NFL. Well ... not really. The Cards need an actual quarterback first. But when it comes to their won-lost record (which is what some would have you believe is al that matters), no team is better than Arizona over the NFL's last 13 games. Believe it or not, the Cards have a lofty 11-2 record over that time, and they're doing it with defense, defense, defense. Patrick Peterson is the best cornerback in the game right now -- sorry, Mr. Revis and Mr. Asomogha -- and the Cardinals' pass-rushers are just short of ridiculous. Defensive coordinator Ray Horton has put together a defense inspired by his mentor, Pittsburgh's Dick Lebeau, but with a few new wrinkles. You'll see Peterson playing iso (no safety over the top) coverage against an opponent's bets receiver every week, and stalwarts like Dockett and safety Adrian Wilson take the playbook on the field every week. it's Arizona, not San Francisco, that currently sports the only undefeated mark...