The Pats in the last two years have ranked 1 and 2 in first downs. They've been an excellent rushing and passing offense both years. They were better on the ground this year than they were the year before - this year their top four rushers all averaged more than 4.3 YPC, and they were at 4.4 overall. If they had a bad offensive line, it didn't show much in the stats. They had good runners so they ran well. They had bad receivers so they didn't pass well. It doesn't seem like the offensive line was a major factor either way. If they'd had Aaron Hernandez and Wes Welker, Brady would have thrown for 4800 yards and 35 TDs again and nobody would be whining about Wendell.
The numbers basically tell us what we could all see with our eyes: the Pats had fewer weapons and Brady struggled to find open receivers, particularly in the red zone, leading to longer-developing pass plays and more sacks. The numbers bear this out in the reduced red-zone effectiveness, the lower number of passing TDs, and the larger number of sacks -- they gave up 27 sacks in 2012, 40 this year. On the ground however they were excellent. This was one of the best running units the Pats have had in the Belichick era.
I compare Wendell to Arrington because he's a player Pats fans love to hate but he actually does a lot of positive things, plays a ton of snaps, and does what he's told to do on the field. If the Pats draft a guard or center who beats him out, that's great. If not, he's not going to kill us out there. He's proven he can be the starting center on a league-leading offense. So has Dan Connolly. Pats fans must be very spoiled to be disappointed to have him back, especially when we don't know the exact numbers yet. If it really is a $200,000 roster bonus instead of $2 million, it's a perfectly appropriate deal and will look even better when salaries skyrocket next year -- the same way Arrington's deal doesn't look so bad now that even borderline useless corners are making twice his salary.