Pats have always drafted well. Also willing to use FA and because of success have got good players who are willing to come cheaper for chance at a ring. Pats also most of time will not overpay a guy on 2nd or 3rd contract. They want to much they move on and draft or sign FA to replace them. The Pats are probably the only team to have been able to replace a guy and most of time not miss a beat.
With Packers TT was just a cheap SOB who valued draft picks over good players and rather have taken the comp picks. That's fine and dandy if you are hitting on a lot of your draft picks but as we saw last 5+ drafts of TT's he was not hitting the broad side of a barn with his picks. So was pretty much letting good talent walk out the door for little to no return on his replacement.