Yeah, I'm also of the mind this is a bit of a reach. Right after a big win proclaiming, essentially, we are going to win the SB isn't exactly ripe bulletin board material.
Not all teams follow the Brown->Belichick rule of, essentially, say nothing. IMHO there probably is a modicum of advantage in following this rule and I am a supporter of the Patriots' method of 100% focus on study-practice and letting the talk get done on the field (with the macro view being every advantage/edge, even minute ones, should be gained). But obviously not all coaches subscribe to this. Seahawks and Steelers are two that come to mind that pretty much give players carte blanche yapping.
Of course which side of it is the bigger edge? Is it the Patriots in general don't yap or is it that the Patriots don't take the yapping bait (when other teams start making guarantees)? That in itself may be the part that gets under a players skin when he yaps yet the Patriots reply is 'they have a very good team'.