Watching most pros, when they go up for a jump smash and they bend their legs, their lower legs are parallel and pointing straight back, with their body turned to the side, so that their shoulders are perpendicular to their waist. But, some pros, and Fu Haifeng immediately comes to mind, when he jumps up, his legs are often facing sideways as well, i.e. his whole body is pointing sideways. Does this produce more power, as it requires more movement of the whole body in mid-air? There's a good photo of him in one of the earlier jump smash discussions where you clearly see him go up and his legs are not facing forwards.