SportsGuy makes some solid points:
Now here's where it gets really good: Pierce, Allen and Garnett happen to be wired the exact same way -- three ultracompetitive guys nearing the end of their primes who would sacrifice anything to play on a winner. All of them were stuck in miserable situations last season (combined record: 87-159), all of them are good guys, all of them understand that you only have so many chances to contend. For all three guys, it will be their best team ever, regardless of who's playing with them. Allen hasn't played with a top-20 player his entire career; neither has Pierce; and Garnett hasn't played with one elite scorer, much less two. For Garnett, his major weakness (crunch-time scoring) gets solved with two proven crunch-time scorers helping him. For Pierce, his major weakness (leadership) gets obscured because he has two intense veterans who know how to deal with the media and lead by example. For Allen, his weakness (a tendency to break down) gets negated because he won't have to carry his team offensively every night.
Just think of these three guys thrown together. All three carried playoff teams further than they should have gone: Pierce in 2002, Garnett in 2004, Allen in 2005. All three were on suicide watch as recently as six weeks ago, wondering how they could extract themselves from untenable (and unwinnable) situations. All three are about to become relevant again in April, May and June. Would you bet against them having monster seasons? Would you bet against them embarking on a 100-game mission to make the Finals? Hell, have three star teammates ever had more to prove in one season?