Just curious - the US Portsmouth system you guys are using : It seems to me that this system promotes the designing of boats that are overpowered. ("They work extremely well in south Florida conditions but will toss you into the main if you let up a small amount")
I`m not familiar with how it all works, but it seems that such a boat will clean up in light air, then when it gets heavy and unmanageable, it will get a corrected rating for higher wind, when more manageable boats are sailing past it.
So it wins on all counts, basically.
I also think having this rating system work well relies on large fleets of all rated classes racing against eachother on a regular basis, this no longer seems to happen anywhere on the planet.
Perhaps the committee who run the system should look into removing classes from the list that are not well represented at bouys racing, if this is where they collect their data. Alternately, if these boats only show up for long-distance races, use that information. The fact that Bill Roberts is regarded by most who know him as a very good sailor would mean that, with your system, the handicap of the SC20 would actually be unfair, but not in favour of the design, rather acting against it, since your numbers are based on skipper performance as well, and Bill is the only SC sailor who races ?
It would be interesting to see what rating this boat were given by ISAF / Texel if you punched the stats of the boat into it. You could then look at averaging the two out, between ISAF & US Portsmouth. That might get you halfway to the truth, and a little closer to reality.
I`ve heard that the ARC17 Bill launched a while back is also a "ratings beater", seems like Mr. Roberts has figured out how to design fast boats that "appear" to be slower ?