"Also - the Prosail 40s were not one-design in the sense you say. At one point there was trimaran in the mix."

After checking, I see that ProSail started with the Hobie 21s as Mary says, then built a "fleet of Formula 40s albiet a semi One-Design" very similar to Smyth's M&M that won the F40s in Europe in '86.(Seahorse mag Nov/Dec '88)

After the first event in '88, the lovely Gougeon tri Adrenalin joined in. According to Seahorse mag March/April '89, the series went OD after that, using ProSail 40s designed by M&M (the first three were built in '88, another for Smyth '89, and some of his earlier F40s were changed to "convert them back to the ProSail 40 specifications". The M&M website says that "the Morrelli F-40 became the Prosail one design choice in 1989 and 1990."

So it seems the series was (with one exception, Adrenalin, which was banned after 2 events, and perhaps the less successful Earthwatch?????) One Design.