I've just started driving a different truck with a 9LL tranny. For the last few weeks I've tried shifting without the clutch but I'm not getting any better at it. Guess I'm used to the 10 speed in a more powerful truck and I just can't get into the groove for this truck..the power band is from 1300 to 2000 rpm. Last few days I've started using the clutch for every shift and have become comfortable with it.
Moral of this story...just because you see pros floating the gears...do whatever works for you (and doesn't break equipment)