It's laughable the way Pats haters attack Brady as a product of Belichick and Belichick as a product of Brady. I do think they can win with Garappolo, but that's because I think Jimmy is pretty damned good and has bought into the level of preparation needed.
The stuff that impresses me (as it does the Eagles fan who chimed in) is that they have done this through massive roster shakeups and changes all year and every year. They lost the best Tight End in the game. Last year lost Lewis and Gronk, and Edelman. They dumped Collins this year, who just became, I think, the second highest paid defensive player in football. The defense got better this year when they plugged in Kyle Van Noy (who?) and Shea McClellan (who?). They let Wilfork go and plugged in Branch. Let Revis go and replaced him with an undrafted CB from South Alabama.
What I've come to understand from people who have come through New England and left, is that the level of work and preparation they do is unprecedented. Guys like Marvin Harrison, a HoF receiver, come in and simply can't even hack it and quit. You can win with talent without that level of effort, but the structure of the league will ensure that you can't retain that talent level. So other teams come and go. Dallas is now loaded. Oakland looks pretty loaded. Houston is loaded on defense.
Brady is who he is in part because he shares that work ethic. Belichick seeks out other guys who have the traits he wants, even if they aren't the most talented guys. It's fascinating, really, how often he's done it.