I think it is the weight gain more than anything that has affected his explosiveness. He looks to be 20-25 heavier than during his Orlando days and he certainly looked "sloppy" by professional basketball player standards last season.
You could tell a major difference in Tmac before he went to the "witch" doctor guy (I always forget his real name). I remember the first time he did, and he played his first game after that, the rockets announcer guy (not clyde) mentioned that he jumped higher on his jumpshot. You can still see the explosiveness (although obviously it will never be the same as a couple years before-he is getting older) The bad back definitely bothered him during the early the stretch of the season and you could see it too. Unfortunately, as it is a chronic problem, it will probably never go away, and I think sometimes Tmac gets bothered with thought of that damn back and thus doesnt attack the basket with as much ferocity or explosiveness because he is always so hesitant.
