A reiteration of aims

The idea that in nature, for the preservation of energy and to aid and avoid predation in any fluid, liquid or gas, the presence of a rounded front and pointed tail, is fundamental.

The sheer instability obvious in the mono-hull I built rather puts a single hull out of the picture in the matter of building  a fast and cheaply built cruising sailing boat. But that fault, its lightness, may indeed be it's salvation when used as one of a pair in the building of a catamaran. 

The success of catamarans on skids and thus low wetted surface areas was shown in the last America's Cup. Their instability however was also sadly demonstrated with the loss of life and it must have struck many as obvious that in heavy weather of any sort purchase on the sea and thus stability was going to be pretty precarious.
Here the use of two hulls, made similarly as the one before, from a single sheet of metal, means they can be absolutely identical and such reinforcements as needed on the sole of the hull or any other part can be identical and utterly flush as there is no 'belly or 3rd dimension' to it. Those reinforcements should leave no gap and riveting them in place with perhaps a thin lay of silicone filler should offer a very sound strengthening.