You and your fellow Nostradumbasses on this board have been saying that for several years now.
The LBs (or, at least, Bruschi and Vrabel) are old, certainly, but still playing at a high level. And Colvin and Banta-Cain are not old-timers by any stretch of the imagination.
The secondary seems neither excessively old nor young. Along with veterans like Harrison, Chad Scott, and Artrell Hawkins are young players like Asante Samuel, Ellis Hobbs, Eugene Wilson, and James Sanders.
The DL, which is among the best in football, is very young (Seymour, Ty Warren, Wilfork, and Jarvis Green all drafted in '01 or later), and locked up for many mere years.
Not sure what roster you're looking at, but the Patriots' defense, on the whole, is not too terribly old.
This doesn't mesh with your consistent criticism of Brady.
Is Brady horrible, or does he do more with less than any other QB in the NFL? You'll have to decide.
Criticizing a QB for his play in a game in which he threw 2 TDs, didn't turn the ball over, put up a 101.5 passer rating, led his team on five consecutive scoring drives against a solid defense, and got his 11th playoff win in 12 games just makes you look foolish.
He played very well at ILB before his injury.
Yeah, it was. His play helped to solidify the LB corps early on.