It's certainly maddening to watch at times, but BB is a conservative defensive coach and would prefer to force the other team to beat him than to send an array of blitzes that could get torched like we've seen Brady torch Rex's Jets more times than not.
I think the traditional Fairbanks-Bullough 34 is, for the most part, dead. It's too hard to find the three down lineman who can all two-gap but also get pressure. It's also somewhat dated now because of the prevalence of passing attacks. The Pats defense now is almost more of a 2-5.
The last time I can remember seeing it was on the fly against Tebow and Broncos in Denver in 2011 when the Pats were getting run over. So now it's more of a specialty thing to stop the run.
Read-and-React is a vestige of that old 3-4, in that the DL hold up their OL counterparts, and the linebackers read the play and flow to stop it.
However in the context of the secondary, read-and-react gets lumped into zone coverage and there's no question that the Pats were far too zone-heavy in recent seasons until they got Talib. It seems like they finally got the message that you must be able to play press man in today's NFL, because the QBs are just too good and even the average ones can pick apart zone defenses.
BB coaches a lot of pattern reading which is a form a zone, but not just dropping to a spot. It's about understanding route combinations and jumping them. Asante was deadly at this, but it's better to mix and match man and zone pattern reading.
With better talent in their front seven (hopefully with Kelly/Wilfork, Armstead, Mayo, another sold defensive end) and Talib back, the Pats should be as well-stocked on defense as they've ever been since they were winning Super Bowls.
