The problem with the Pats defense is that they have lacked a true impact player for years now. In the immortal words of Rick Pitino, "Rodney Harrison/Richard Seymour, Tedy Bruschi, Mike Vrabel, or Richard Seymour are not walking through that door".
BB has tried to fill holes, he has made some serious swings and misses at DB. I think he made a major mistake not keeping Branch a few years ago (and of course in drafting Merriweather with the Branch pick).
But in the end, it all comes down to when its crunch time, the Pats do not have a guy on defense that will make a play. How many times did Rodney, Bruschi et al come up with the big play when the Pats needed it? That is what has been lacking, IF the defense had come up with 3 stops, the Pats would have 3 more titles.
So now the job is to find a playmaker on defense. Move up if you have to, NOBODY drafted after the 4th round is making the team, so do some bundling and get a playmaker. Of course, this will almost guarentee another trade back, pass of player X for an additional 3rd round pick that they trade for a future second round pick, that turns out to be Butler, Brace or any of the other busts that litter the Pats recent draft boards.
It's not about playmakers, it's about overall talent. The defense has been in a state of decline since 2007, and that should not be surprising to anyone. The old guard was gone or going, and the new blood was not up to the task of replacing it.
From 2005 on, when the team knew it was going to have to start looking for new defenders, here are the defensive draft picks and the round taken:
2005 -
James Sanders (4), Ryan Claridge (5)
2006 - Jeremy Mincey (6), LeKevin Smith (6), Willie Andrews (7)
2007 -
Brandon Meriweather (1), Kareem Brown (4), Justice Rogers (6), Mike Richardson (6), Oscar Lua (7)
2008 - J
erod Mayo (1), Terrence Wheatley (2), Shawn Crable (3), Jonathan Wilhite (4), Bo Ruud (6)
2009 -
Patrick Chung (2), Ron Brace (2), Tyrone McKenzie (3), Myron Pryor (6)
2010 -
Devin McCourty (1), Jermaine Cunningham (2),
Brandon Spikes (2),
Brandon Deaderick (7), Kade Weston (7)
2011 - Ras-I Dowling (2), Markell Carter (6), Malcolm Williams (7)
DraftHistory.com
That's only about 7 players who've truly flashed at, or near, starter level, for any real period of time, and 2 of the 7 aren't even on the team anymore.
From 2005-2007, BB was building the offense with high picks, and the defense with low picks, and that strategy meant that almost no new defensive players were being added to the team. The team was still being built with veterans, but the quality of free agent veterans was in decline because teams had gotten more adept at managing the salary cap (and the increases in the cap made such management easier).
2008 was the first defensive draft in years, and it turned out to be a major flop, as the only one of the 5 picks to be of any real quality was a top 10 overall pick, and the rest of the choices (2,3,4,6) washed out.
The jury is still out on 2009, but the early results don't look good. As of now, only Chung has established himself.
When you've got that level of struggle in the draft over that period of time, and you aren't making up the gap with great free agent signings, you're going to have problems. It's not about playmakers. It's about having very few true defensive draft hits in the last 7 drafts.