Bill Barnwell is a pretty good mouthpiece, but that's all that he is. For better or worse, he basically just parrots Football Outsiders stats. The next original thought that he expresses in a Grantland column will probably be his first. The only quasi-compelling point that he made was that tight ends are generally more injury-prone than WRs, which has been common knowledge since forever.
As for whether the emergence of the tight end is a fluke... of course it's not. It's a direct response to the decline in running the ball across the NFL, and the resulting tendency of guys like Rex Ryan to flood the field with defensive backs. If nickel is the new base defense, then of course you want a 6'7" ogre who's too big for DBs to cover, and who can also help clear a path to plow right over them in the ground game.
I don't understand why anyone's treating this as a flash in the pan; innovative minds have been searching high and low to find game-changing tight ends for years. The only difference is that now they're actually finding them. There's a reason why Belichick has drafted 7 tight ends since 2002, including two first rounders and a second rounder. Ever since Tony Gonzalez worked out, other teams have all but resorted to dragging guys off the basketball court.
Will Gronk catch 17 TDs every year? Of course not, and I hope that nobody here needed Bill Barnwell to tell them that. Will his body break down in his early 30s, if not before? Wouldn't surprise me. But so what? The article's insight into the matter basically consisted of naming three examples, then two counterexamples, and calling it a 'disturbing trend'. Let's just say that he didn't exactly blow the null hypothesis out of the water, especially when two of the three guys he cited played in an era where a torn ACL was a career-ender. His larger analysis, by ignoring players who haven't yet retired, is similarly skewed.
He did miss a cool opportunity, when discussing the 'undervalued assets' perspective, to tie it back to Moneyball. This same exact phenomenon is well-documented in the MLB. After the A's had some success, Moneyball came out, and big-market teams started hiring Billy Beane disciples, everyone started going after high OBP guys. Why? Because that's what Moneyball had been about... except it wasn't. OBP happened to be the stat that Beane had correlated to winning that happened to most undervalued in the market at the time. So every front office that took that takeaway from Moneyball was learning exactly the wrong lesson, because within a couple of years OBP was intensely overvalued. Look at Oakland now - they aggressively pursue defense, because it's extremely undervalued at the moment.
The Patriots are Billy Beane in this scenario, except they're not crippled by having to compete with one quarter of the Yankees' payroll. Everyone who's trying to play catch up by snatching up tight ends in a seller's market is, again, kind of learning the wrong lesson. They're right in that tight ends are a valuable commodity against DB-heavy defenses. They're wrong in that tight ends are no longer undervalued. Foresight benefited the Patriots in a huge way just to get Gronk and Hernandez, but they're probably going to have to pay more than they originally anticipated if they hope to keep both of them.
Anyway, it's actually pretty easy to strip out all of the filler and distil this article down to a couple of (admittedly awesome) sentences:
If you want to run your team like the Patriots, you don't steal what the Patriots are doing now. You steal what the Patriots are going to do next.
Good news for the rest of the league - that's the blueprint right there! Now you just need someone as intelligent and visionary as Bill Belichick to pull it off.