From where we're sitting, the answer is pretty obvious: Why not?
This is why adding a dynamic player like Harvin should seem like a no-brainer. He can add firepower to an offense that already out-dueled the best defense in football. He can take some pressure off Brady and put limitless possibilities on the table for offensive coordinator Josh McDaniels.
It's easy to say that because Harvin has a questionable reputation, New England would be the perfect fit. We have no way of knowing whether that is true.
But it is pretty easy to say that Belichick would not be criticized heavily for swinging and missing on a move like this based on his track record.
And if you have the chance to add a dynamic 26-year-old wideout heading into the prime of his career, why not do it?