I can only agree with everything you just said - its spot on. I have seen many fights of both, but it doesn't really make it much easier.
This is gonna be a great fight. Two top fighters meeting in the ring, in a match that, going in, could go either way. I happen to think that Calzaghe is gonna dominate, but if he's slipped more than has seemed apparent, it is possible Kessler could beat him. I doubt it, though. Calzaghe by wide UD