Yes it works. I have witnessed it being done several times.

Yes, we saw the flat version at the Alligator Warrior Festival with the "Seminoles" in their village cooking over logs in a cross shape using the same principle. In fact, the cross might be a better method because the other skillets and cast iron gea can be set on the arms of the cross and kept hot from the radiant heat of the still-cooking item in the center.

and cool for lights, have seen them at Luau's on the beach between Tiki Torches 8)