[naitsirk0]

I'm pretty sure they are the same, like two sides to the same coin.
When his hollow has more power - hichi plays, when his shinigami has more power - zangetsu plays.
But as it's been said before, ichi's bankai is really new, and judging his growth rate so far I think it's safe to say that he's doing pretty well don't you think?
He may only have one move (which he now uses differently to make his swings stronger) but meh, give it time, other captains have had hundreds of years (or less) and come up with these random moves, he's had it.. meh? a year? yeah..