The Red Sox have a completely different FO. The fact that he on bad terms with the old Red Sox FO means nothing.
Basically, what you're saying is that Clemens would go back to New York, because he likes the fans?
On that logic, why wouldn't he sign with the Astros? Or, the Red Sox? If he comes back to Boston, Bostonians will rename the city after Roger Clemens.
So far, the Yankees have shown no flexablity to give Clemens the days off, when he does not start. The Red Sox have gone to the lengths of offering Clemens, John Henry's private plane.
Also, he has nothing left to accomplish in New York. He's already won a Cy Young, and a World Series.