2) offer a trophy for the oldest boat that completes the regatta.
Stereotypes run really deep on this site.
Just because there are a lot of old Hobie 16s out there doesn't mean they're racing competitively. At the Hobie 16 North Americans last year (at this same venue), there was 1 boat older than a 2007, and they didn't do very well. The vast majority of boats were less than 3 years old.
