The HH are made from a rectangular piece of fabric, just like all the other hammocks I have made. Mine was ~60' x10' using the dimensions given on the HH website. The shape aysm shape is defined by the roll whip, side tie outs, and the netting. The whipping mostly effects the way the hammock lays more than the shape. If I don't use my side tie outs the hammock looks just like a Speer. One the side tie outs come into play it takes on the HH look and shape. Ed Speer mistook my hammock for a HH when he first saw it at the last SEHHA I attended.
Arkwater experimented with a trapezoidal shaped piece of fabric. The thread is here:
I also tried the trap. shape with some simple folding, but I prefer the roll whip to all other methods I have used so far.