heres ur answer
if u read the descriptor i think you can safely say the guy who came up with it has no idea what he is talking about or any experience with stand up dh skateboarding
I'd be guessing but there is minimal level contact with the ground and that is directly under your centre of balance. By the time you add three or four feet of crouched rider above that single point of contact, I think it would be a little unstable. If you then bring it into cornering your grip would be good on the inside until the projected centre of balance but non existent thereafter, which you still get with a standard truck. Personally I wouldn't be seen on it, but you gotta give the guy points for trying. It's definitely a creative leap.
If i saw that at the top of a hill with a "ride me" sign next to it i would have a dig for sure.Pad up and test pilot away.
Curve extreme people hint hint ! Send me one : )