Have to pot in and tell you how much I enjoyed this well thought out and articulated thread. Good football talk at its finest. If I may here are a few comments.
1. I think its important to repeat this comment. The Pats LB situation is different from most teams. It is not something that an inexperienced professional can easily adapt to. Look at the Chad Brown example. Here was a very good LB with a lot of Pro experience, including the Pittsburg 3-4, who was, for the most part, lost during his time here. So was Beisel, whose regression still baffles me. Ergo, drafting even a talented LB out of college and expecting them to do great things in this system is a bit unrealistic.
The other reason, which was stated in this thread, which makes finding good LBs for the Pats, is that projecting how a college LB will do in the Pats defensive system is VERY DIFFICULT, and problematic. That iswhy we can expect the Pats to continue to take shots at low round college LBs/DEs who they can hope to develop into suitable players, all the while understanding that they will have many more misses than hits. AT THE SAME TIME going to FA for more experienced and more easily evaluated player, who STILL may or may not fit the system.
The best example of that "mystery" is WHY Junior adapted to well to this system so quickly, while a guy like Chad Brown, had so many problems. Both were good, smart, and experienced. One guy adapted, one didn't. Understand that this has nothing to do with the physical ability of the player, but with the mental adaption to the system. I have no answers to this 'mystery', BTW. Its just an explaination for why the Pats operate the way they do in finding ways to fill their LB roster spots.
BOTTOM LINE here is what I expect the Pats to do this off season. They will probably draft a DE/LB type or 2 in the second day, and go after a couple of mid level to upper level FA LBs. My personal fantasy would be to see Lance Briggs in a Pats uniform next season, but for the many reasons we all know to well, this is what it is.....a fantasy.
2. I remember TBC from that draft. IIRC, most draft sites were projecting him to be a 2nd to 3rd round pick, so his percipitous drop to the end of the 7th round was a mild surprise. IIRC it was due to an off season surgery or injury, because I'm pretty sure he was on the PUP for a great deal of his rookie season.
As for his progress he is pretty much on course for the "typical" conversion of a college DE into a finished product to play in the Pats LB system. IMHO this is a 4 year transition at minimum. I'm also pretty sure that the Pats wouldn't have let Willie go, if they didn't think that TBC wasn't progressing at a pace that would make them comfortable. So far, I don't think he has disappointed. Remember that the way the Pats play defense, it is really difficult for ANY ONE MEMBER to stand out over the course of a season. Guys like Alexander/Woods are still far from finished products and shouldn't be expected to be ready to play for a few more years
3. Finally, its worth repeating, the Pats 3-4 defense, is DIFFERENT than most of the other 3-4's (ie Pittsburgh) that are being used in the league.