Mark,
My opinion is the US F16 Class Assoc should send a letter to US Sailing disapproving of the mandatory membership requirement.
As the North East F16 Representative on the U.S. Executive Council that's how I would vote, but I have not heard much discussion on this within F16.
I am not a US Sailing member and never have been. My personal action will preferably be to boycott races requiring membership, just on principle.
However, if my local yacht club that sponsors weekly evening races follows CBYRA and makes it a requirement, I may have to give in.
Patrick