I believe Dan Kulkoski is the official Measurer and is usually assisted by Kathy and Chip Short.
Sails are measured once and registered as measured and the sail is signed.
I really don't think anyone will show up at the regatta with an unmeasured sail.

The idea of after-market sails was designed to make racing more one-design. The cookie-cutter idea of one factory sail size and shape would not be good for folks on either end of the weight and ability spectrum.

Heavy Sailor = full sail
Light Sailor = flat sail
Excellent helmsman = flat sail
Helmsman not always on top of it = full sail

and the list goes on.

It has seemingly worked. We now have two women that won the Open Nationals -- Kathy Kulkoski was the first and Leah White, this past year -- my Daughter-in-Law.

We have also had small guys win (Paul Garlick) and big guys win (Rick White)

Rick