And in a perfect rating system this nature would be well represented by the formulas. Of course, a perfect system does not exist, but in the case of the 16 the schrs does not work well, whereas with more similar boats (F18-T-A) it usually works out fine.

This could indicate for example that the factor applied to centerboard area and aspect is too small. Or maybe it would be nice to have a factor that controls if we have a more efficient rig (with diamonds, controlable mast rotation etc.) which permits more control and therefore permits a sailcut that powers up with less wind.

I guess the influence of these systems on the survival of classes is probably underestimated. A good 16 sailor here gets bored going to local races if he has no chance to obtain a good position. So he only has the national races where we have a 16-only fleet. Given that there are much more local races during the year, he will have more fun if he gets another boat for racing (F18, A etc.). He finally sells the 16 and both the local and national H16 fleets get smaller. That is what seems to be happening in Spain right now.

Wouter, I think a good rating system should try to adapt itself to the existing boats and not vice versa. Texel, although simpler, achieves this probably better than schrs.