Thank you Jeff. I wish I could say that I understand this stuff, but I have only a vague grasp and can be readily influenced by logical sounding information.
Perhaps I don't need to worry too much, as I can't really afford a boat less than 30 years old!
I've spent most of my time on wooden sailboats with full keels, so I have no comparison. I am however quite interested in the fin keel concept.
In the non-consecutive pages of the book that I was allowed to look at, I had the impression that it was not the surface area of the keel that was so helpful. It was the linear length (bow to stern), which when running downwind put the different parts of the keel in different (and differing) parts of the wave motion, thus no one part has such a great effect. Plus the old style V hull went deeper, divers know that just a slight increase in depth greatly lowers the wave motion effect.
Of course, I can't help thinking that very deep fin keels would also reach down into less violent motion.
Have you any suggestions on a good place to look for newer information? And are computer models a big part of the new design? I'm a bit suspicious of computer modeling at the moment. We just had a long winter of totally failed computer modeling of atmospheric motion, which gave very poor weather predictions, the worst I've ever seen actually.