Also, in looking at the connection between sacks (pass rush) vs. 3rd-down defense, there's a pretty stable connection. 8 teams finished in the top 12 (I use 12 because 3 teams were tied for 10th) in both categories, plus KC, which finished T-10th in sacks and 13th in 3rd-down D. The other 3 had some poor secondaries (Philly, Tennessee, Lions).
The inverse is similar. Of the bottom 10 teams in sacks, 6 finished in the bottom 10 for 3rd-down D, with a 7th (the Colts) 1% away from finishing bottom 10 in 3rd down D. Of the other 3 teams, 2 had pretty good secondaries to help make up the difference (Washington and Cincinnati). The 3rd was Baltimore. Some might include them in the above group as teams with solid secondaries, but they have an overall good team D as well with everyone doing their job. Interestingly enough, for all the talk of the Ravens having a proven pass rusher in Suggs (11 sacks), they finished with 9 fewer sacks than the Patriots.
For all the whining and complaining about the pass rush, the Patriots did finish 14th overall in sacks with 36. However, they were absolutely atrocious in 3rd-down defense. But was it because of no pass rush? We were middle-of-the-pack in sacks. We should have been close to that in 3rd-down D as well. So I don't think it's fair to blame the lack of pass rush. It could be better, sure. But that's not why we struggled.
In looking at the outliers of both top and bottom, the secondaries seem to matter a lot. And in 2010, our secondary consisted of a rookie, a Pro Bowler everyone hates, a 2nd-year guy taking over a starting role, and a 2nd-rounder who struggled or an UDFA STer who hadn't played many meaningful minutes at CB. McCourty was a star, no doubt about it, and Chung shows great potential. But they're all young kids who are still developing together. If McCourty hadn't made so many big plays, this group would have been seen as terrible.
The secondary gave up the 3rd-highest passing yards total, tied for 5th in highest 1st down % by pass, and 9th-highest completion %. The TD to INT ratio was 25-25, as we led the league in INTs, but without McCourty's contributions, these numbers look a lot rougher.
The return of a healthy Bodden combined with the drafting of Dowling should dramatically improve the other side while also upgrading our nickel/dime. A full year of experience for Chung and McCourty should also go a long way towards improving our woes in the secondary, which should at least put us around middle-of-the-pack, which would be a dramatic improvement.