Like Belichick has said, a combination of factors led to this move. Based on everything we've heard so far, I think we can logically reach a few explanations for the Randy Moss trade, in no particular order:
1. Moss' inability to run all the routes in the Pats' offense. Sure, he could run all those slants or quick outs every play, but he's not going to be effective doing it. That's not his skill set. And since he's double-teamed on all of his deep routes, that's a side of the field that's practically never open. He doesn't have the versatility Belichick wants in a receiver. As others have pointed out, that limits the options the playcaller has.
2. They weren't going to re-sign him for the above reason, and on top of that Moss isn't getting any younger. He's still a great receiver, but not in the same form as 2007--which significantly hamstrings the style of offense NE was running until this year.
3. Moss knew the Pats weren't going to re-sign him, and while he was a good locker room presence, his contract situation could have become a potential conflict as the season got on--something demonstrated by his behavior after the Bengals game.
Therefore, it was decided that the best move for both parties was a trade; for the Pats, to avoid the future possibility of late-season turmoil, and to get compensation higher than a 5th round compensatory pick; for Moss, to move to an offense where he would again be the featured wide receiver, which should help him earn a larger contract either this year or in 2011.
