That's not that far off what Tall Paul did after all.

First off I think the tips being angled like that will function much like dihedral. But for the airplane to have any roll control it MUST be moving forward so that the yaw can act on the angled tips and roll the model In a hover it won't work that way. In fact the rudders being on the upside of the model will tend to roll the model in an adverse manner instead of pro. But in truth they won't even do that because as Paul said you MUST have the controls in the prop blast during any super slow harrier type flight and especially for hovering.

As for the airfoil there's so much cut away that it won't operate as an airfoil at all. It may fly just based on light weight and body area but it won't be pretty if the engine quites. And the flat bottomed airfoil rements are going to have all sorts of pitch to speed coupling problems. He would be way better if he used a symetrical shape.

Bottom line? I truly think he's not thinking the factors out very well. It may fly but not in the manner intended as you described it.