There was a guy named Adam Karpowicz (sp?) who used to make bows similar to that, I remember reading an article in the magazine once that he wrote about them. Seems like he was trying to get nearly zero brace height and long draws from short bows or something like that.
Karpowicz experimented with hornbows the way you describe; such a bow is pictured in TBB4, and his experience with it is described in detail at ATARN.
Honestly, I don't think this ebay guy's bow won't make it into TBB5...!
If the bow of the ebay guy had a side profile with let's say the working part being straight and the recurves being angled the way they are, there was no way to get this thing to be stable.