Well, that's why I said it was an assumption on my part! 
I've never seen anything that said he can only use his jet pack to go forward . . . then again, I never saw anything to the contrary either.
As far as the balls comment go . . . . well, just look at the original prop . . . even the one that Jango wore. The thrusters are connected by an axle. They can spin, but in one direction only.
I dunno . . . I could be wrong (it's happened before) but . . it all just seemed kind of hokey to me.
Jer
