Re: How do you feel about catamarans?
Had a fair amount of back and forth with the gentleman from England who builds the JSDs calculating exactly how many cones my vessel would require. He constructed a second series to attach to the first also calculated minimum weight to stick on the end. That said the device does greatly increase chance for survival and does allow you to lash the helm amidships and go below with the boat passively enduring the storm. This also increases odds you and your crew will survive. However, there are potential boarding seas and then there are breaking seas. The breaking seas I've encountered are not always predictable. Nor are they always coming the same as the rest of the wave train. Nor have they come up to the boat at the same speed as they prevailing waves -in fact usually they are travelling faster as they break. Even when surfing have been pooped. Admittedly mildly so as this occurred in a gale not a storm. Have had a prior boat completely submersed from seas boarding while hove to in a storm but nothing blew out ( other than the Sargent strips on my and my co owners pants until it was over(grin))However, although I agree with everything you've said I think the JSD does not prevent pooping by breaking seas and boats should be designed to survive such occurrences. As Jon said this is equally true for one hull or more. I just wanted to point out due to nature of design with much wider houses this is potentially more of an issue with multihull vessels.