I rode a tri very similar to what you're proposing, a few years ago on Lake Minnetonka, MN. He was a budding naval architect, and custom built the center hull, either 20 or 22', quite low profile, very similar to a tornado design. He used 2 Nacra hulls, I'm not sure which ones. Round aluminum crossbeams, maybe 18' beam. The rig was from the Nacra, if I recall, and as such seemed a bit undersized, until we took it out. I was quite impressed, mostly with the whole different feel than the cats I've experienced. Very stable, not twitchy, accelerated easily, little heel (not sure I'd ultimately like a boat that didn't fly a hull) . It seemed deceptively fast, even with what I thought was an undersized rig.
Only got that one ride, an hour in maybe 12 to 15 kts of wind, less than a 1' lake chop. I remember it well, I was intrigued. I think you should give it a go, and keep us posted.

Dave
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