Well now Bill, you ask :

"So, Larry, what's new??? Where's the new technology? Where are the breakthroughs?"

Two give three examples :

Squaretop mainssails
a 20 footer weighting in a 115 kg = 254 lbs (m20)
reproductivety of hulls within 400 grams (1 lbs) or less when using prepreg materials.

May not be breakthroughs in the purest sense of the word but significant advancements just the same. You yourself just quoted the development in the Tornado class in a recent class where a wobbly boat of 450 lbs was transformed into a very stuff 375 lbs boat with a long competitive life.

That is all new and one couldn't do these tricks 20 years ago simply because the technics either didn't exist back then or were still far to expensive to be used in anything other than space flight.

Than we have the introduction of the Flyer hullshape (the original shape, not the copies) which pretty much took the A-cat class by storm. In the late 80's early 90's the a-cats went down from 100 kg's to 50 kg's overall weight. Now the min weight is fixed at 75 kg but they can be build lighter.

I can't remember but when was the prebend rig developped in the tornado class which is improved the control of the mainsail and increase the area in which the mainsail could be trimmed to it's optimal shape. I think it was done in the 80's and perfected later.

I've heard people say that ARC designs can be summarized by "stack more sailarea on it than others do and go faster". What have we seen in the last 20 years ? We've seen smaller boats with limits on sailarea go faster and faster and equalling the ARC design but innovation and advancements in catamaran design. To get more out of less is called progress, just like how modern race car are faster than their banned 80's turbo charged predecessors despite the fact they don't use turbo's anymore.

Then you indicate that :"Spinnakers have been around for 50 to 75 years or more"

Yes, but the asymmetric spis on cats are cut complete different from the symmetric spinnakers of 50 years ago. Your statement is analogue to saying that nothing new was devellopped over the last 3000 years as catamarans still use soft sails to propel them forward. In that respect a ARC is nothing more than a pre christianity polynesian proa made out of fibre glass.

I for one would like to see someone cut the transom of a SC19, put a rig of 21,15 sq. mtr. with a 80's cut (pin head) on it together with a spi that is cut like the ones of 50-75 years ago and do well against modern F18's in the F18 world cup.

I think we all know where this boat will end up and that proofs that there really has been improvements, developments and innovations over time. The may have been spread ou over a longer period of time and therefor can't be really described as breakthroughs but a modern cat is certainly not more of the same old 80's technology.

Maybe extending the transom of a SC17 to 18 foot would be a better comparison to todays F18's ; Weight and rigarea's are far more alike.

Wouter