The variance in the finish times of the top 5 finishers of a one design class is about 2.5 to 5 %. This has to do with sailing skill and luck. It's the intrinsic variance in the game.
So performance based handicap ratings between different classes will have a limited precision as well and won't resolve the subtle changes in design that develop over time. It will take a lot of data to get this level of precision around an accurate rating. If a game changing innovation shows up while you could detect it in the results quickly, the PN system would adjust for that change over three years by the standing policy. Also... you would need a lot of data to measure a significant difference.
You suggestion to combine the two methods presumes that something is wrong with the current measurement rating set that must be fixed. I don't see that example in SCHRS or TEXEL You argue that design will lead to game changes and I don't see any game changers in the formula classes... In fact the curved A class boards proved not to change the game as far as the top guys in the class are concerned. Nobody is talking about the new Hobie F18 as a game changer.
Why change?
Sailors don't care about the race results being fair next year... they care about the race they just completed. If it's not fair... it's not fun and they won't be around in three years when the fair result could be calculated. For a new racer starting with an old design... it is tough enough to get up to speed to sail to their rating. If they think the ratings for the hot new boat are unfair.... its another barrier to keeping them in the game.
An alter Qualifer event is very difficult to handicap with a Hobie 14 racing against a Tornado or supercat 22 by design. Throw in rarely raced designs like the CFR 20 and the Marstrom 20 and its really tough to do this job fairly.
IMO a measurment rating would be fairer. I have come 180 on this one and Carl Roberts and Wouter Hinjck should have a quiet giggle here. Dave Inham and I disagree on the basic premise of handicap racing so he can't giggle. he doesn't like the whole idea. (grin)
