Not sure if you've seen these, or if they were mentioned in another post...but someone did something very similar to what you're talking about, albeit on a much smaller scale:

http://balancedrig.com/

Phil

--- In harryproa@yahoogroups.com.au, Gardner Pomper <gardner@...> wrote:
>
> Hi,
> This is probably a dumb question, but what is the problem with a "gaff"
> easyrig? By this I mean an easy rig with a boom at both the top and bottom
> of the mast, so that both the jib and main are rectangular in shape, instead
> of triangular? Everything I read indicates that a triangular sail is
> inefficient, and that more sail area higher up is better. I have seen solid
> wing sails in this configuration.
>
> I know weight aloft is a bad thing on a monohull, because it intensives the
> pendulum effect m the inevitable heeling, but on a multihull, which should
> never lift a hull (cruising, not racing proa) it doesn't seem like it will
> matter until you are in alot of trouble anyway. Plus, having a rectangular
> sail should lower the center of effort considerably, to keep you out of
> trouble.
>
> Anyway, basic explanations of why I am wrong would be appreciated <grin>
>
> - Gardner Pomper
>