There are always exceptions to all rules, With F20 it is my most passionate hope that there will be more boats racing as a class than before. In the last 3 years of racing I have yet to race more than 4 (very recent) boats in my class, I travel over 10,000 miles a year to race but still there is only very recently been a trend towards the I20. There are about 20 Hobie 20s in the region with at least 5 at a time at most regattas. about 4 N 6.0s with one avarage. there are almost no Tornados at any of the regattas I have been to in 3 years. (one at one race). So excluding such a small minority is not much of an issue. (I have not seen a Tornado entered in the Tybee,or atlantic 1000 but I might have missed the one or two that have.) maybe there could be a F20ht class. But one thing at a time for me.
As far as europe and the world vs. the US. well if we get a class going here and it takes off then if anyone wants to come play we can try to work them in at the time. but it is an impediment to movement to try to make it work for everyone before it works for us,(not US ).
another issue is the Hobie 21,(with HS) I think it could and should race F20 but then again that would be up to the skipper if he wanted to shed the numbers advantage.