I'm not sure I agree with you, Mary. It is incumbent upon the organizers to do their best to provide a safe event for the participants, and this would be part of their diligence.

I'd be willing to bet there are some enterprising attorneys who will claim the organizers were negligent in allowing uninsured boaters out on the course

I would not like to be hit by someone without insurance, especially if someone ended up hurt.

Should the PRO require certificates of insurance for all participants? In an anal retentive world, yes.

In reality, if the NOR requires participants carry $100,000 in liability coverage, and the sailors sign the registration attesting to that fact, perhaps that is better than nothing.

With as much litigation as there is in the US, it would seem like a no-brainer. Besides, liability only policies (they don't cover theft or damage to your boat, but cover your liability towards injury or damage to someone else's boat) are CHEAP (like $100 per year?)