I think I have seen photos of that same one, jackcrafty. The main limb is braced against the shooter's feet and is parallel to the ground, the smaller limbs on the ends of the main limb are at right angles....more like the letter H then an X. If I remember rightly, that guy has set some incredible records with that contraption.
It looks perilously close to a compound bow and I think we risk our eternal souls by even discussing it. But a Penobscot/Abenaki coumpound bow is certainly orthodox and venerable!