[AdamHeard]

I'm a big fan of segregating different degrees of freedom to different joysticks. We currently use arcade drive on a skid steer, with on stick for throttle, and the other stick for turning. A human being is not very good at moving a stick perfectly in one axis.

I feel the same way for using the twist of a stick as the Z, that's just way too much for a driver to do with one hand, after all, he has two.

I believe, as chris described, that translation on one stick, rotation on another, is the way to go. This is the most intuitive, and worked great for us on our prototype crab.