I have given all this Wave,F18,HCA stuff some thought over the weekend. I also went back and looked at a number of old results going back to the late 80's. What we see is the steady decline in numbers(captain obvoius here).
So then when asking why, I started to think about the "Fad" of the Hobie product in the 70's and into the 80's(huge numbers). Numbers start to drop in the late 80's and continue to drop through the 90's. Many regattas open up to the X boats as a way to help get by. This went unchecked by HCA and the numbers continued to drop(HCA's fault?)
It appears to me that much of this is just a natural product cycle. The economy was in much better shape all through the 90's and some people spent money on the high tech/expensive boats. They are not doing that right now(I'm thinking about my can't miss Enron stock)
Then the HCA, in an effort to get a handle on it's fleets, sends down the enforcement policy. I didn't like how it was handled at the time and still don't.
(Where am I going with this?)
Sometimes when you need to clean the garage, you take everything out and start over. So the HCA did that and now needs to keep a close eye on what's happening everywhere( I think that is happening). What needs to be remembered is that there are bylaws and a process that can work to bring change.
The HCA is still and should be primarily focused on the Hobie product, but also consider our fellow sailors and find a way to work with them. I think the idea of having guest formula or one design boats at our events just makes sense if handled correctly.

A side note, I was talking to my father who has run the member guest tournamemnt at his golf club for many years. Normally they put up the sign up sheet and it would be full with 64 teams in days with a alternate list. This year the same sheet went up and they have 25 teams over a couple of weeks(HCA's fault)
Times are changing and looking ahead calmly seems to make the most sense to me.