According to Mike Breen last night Curry actually has lost weight (30 lbs) since the start of the season, and is in better shape. It's defintely other things at this point
30? It doesn't look like he lost that much. But he still needs to lose 15 to 20 more. I think he'd move a bit quicker on defense and provide better help defense. He still doesn't see things happen quickly enough and losing weight won't help him learn how to pass when double teamed, though.