Mark,

The Portsmouth ratings work on a RATIO of time between two boats. So if you divide the lower ratings you listed in your post by the higher ones in each comparison, you will see that one is 82.1% and the other is 82.5%. That means the F-18 has to sail the course in 82.1% of the time the Hobie 16 does and the Hobie 16 has to sail the course in 82.5% of the time the Hobie Wave does. So they are essentially the same handicap. Everyone prefers to race one design but since so few race anymore and so many different classes exist, Portsmouth is way better than not racing! The many years we used it in the Ohio Catamaran Racing Association (RIP) demonstrated conclusively that Portsmouth works remarkably well to evenly handicap boats and to encourage more people to come out and race. You only have to look at the dwindling attendance at most remaining regattas to know that we continue to lose that battle...