That's seems kinda unicycle style, no ass in the seat, feels like walking a fencerail to me when I do that, ass in the seat I can hold longer without moving around a bunch. But his bike doesn't move, no forward or back on the rear wheel so if he could do that for maybe a lot longer he'd do alright eh?
As for tricks, my fave is still Butch from Tx, maybe in NC now, juggling while trackstanding, that's harder than juggling on a unicycle