Red zone defense alone doesn't make a team a good defense. Case in point: Miami's defense was tops in the red zone in the league last season. Would you take them over Seattle's defense? How about San Francisco's?
The fact of the matter is that there's more to evaluating a defense than just points. The order that I would put it in is this...
1. Points
2. Turnovers
3. Yards allowed
Most defenses tighten up in the red zone. That's a fact that's widely known throughout the NFL. So to give the Patriots credit for something that every defense in the NFL has a propensity to do because the field gets shorter is simply bad logic. The Patriots did decently in points allowed and turnovers that year, but too many people (such as yourself) dismiss yards because it doesn't work out in their argument's favor. But when you're gaining yards, you're moving the chains. When you're moving the chains, you're taking more time off the clock. When you're taking more time off the clock, you're keeping Brady and the Pats offense off the field. That's what happened in the Super Bowl. Brady's brilliance passing through some of the tightest windows I've ever seen kept us in the game, but in the end the Giants had simply chewed up too much clock, controlled T.O.P. and we were out of the time at the end... after our defense had just had it's hand in blowing the game. You also saw a microcosm of that in the Pittsburgh game earlier that year.
Chad Henne, Ryan Fitzpatrick, Rex Grossman, and Dan Orlovsky all put up career games against that defense. Their teams lost in the end because of the inability to stop the Pats offense. When the Pats played a team whose defense could get stops against the Pats offense (i.e. - winning teams), the Pats lost those games. In the AFCCG, they would have lost if Flacco found the open man in the end zone on one play and if Sterling Moore didn't have the play of his life on another. Why? The defense fell apart at the end of the game.
Further, again, you're ignoring everything the Pats did on that side of the ball in the 2012 draft simply because that pass defense sucked so bad. Since I don't feel like typing it out again, I'll simply copy and paste my reply to Oinko...
Anybody who thinks that that defense was any good that year...
1. Didn't watch that many Pats games.
2. Is blind.
3. Is a HUGE homer.
4. Didn't see the following draft when the Pats went defense-heavy for good reason.
It's either one of those, or a combination of any of them. The pass defense was BRUTAL that year. Second worst all time. After that season, Belichick made some pretty wholesale changes to that side of the ball including: adding a premier pass rusher, adding a rookie LB, signing a safety to a nice-sized contract and drafting one with a second round pick, drafting another pass rusher (that hasn't worked out), and signing an interior pass rusher that lied about an injury and was off the team before the kickoff of Week 1. Do you notice the common theme there? All those moves on that side of the ball were to improve the PASS defense. Why? Because the pass defense was garbage.
For you, I think the issue is that you simply didn't watch too many Pats games that year so, when Tebow became a central part of the argument and the 2011 defense was referenced, you went to NFL.com/FO/whatever and grabbed whatever good statistic you could find about the team, then used it without context. Context, my friend. It's very important.