Good questions!
The class prefers bow numbers, rather than sail numbers. And this seems to be accepted in every venue we have been. The reason is it makes it easier for the RC to catch OCS boats. We have always had rather large numbers at most regattas, i.e., the second Nationals had 64 boats on the line. Now we usually get around 30. This year we were well short of that with 21 boats.
Still the idea that identification is much easier both for the starts and the finishes.

Leah was sailing a stock Hobie sail. So much for the high tech sail argument. Paul Lendenberg, who I have known since 1968 when he won the first Tornado World Championships, had a stock sail and was voicing the same complaint (he has a stock sail). He was shocked to know that Leah was also sailing with a stock sail and had much more boat speed than past National Champ, Patrick Green (sailing with a North Sail)
And, Paul with a stock sail, took a bullet in the regatta as well.

So, the theory of stock v. after market goes to hell in a handbasket very quickly.
"Don't fix the sail, fix the loose nut on the tiller."

Personally, I race against Dave (my son) and Leah all the time. Both use stock sails. I always have a Calvert. I win about 1/3 fo the races, Leah wins over half the races, and Dave wins the rest.
I think the stock sails are so ugly it hurts my eyes. I like to see a good looking sail. It may not be faster, but I feel better about it.
And the cost of an after market sail is not a monumental investment. The Calvert Sails that we sell run a bit over a thousand.

Hope to see you there next year. And I hope I can get to Indy for one of your races this year. Hopefully, no more conflicting dates.
Rick