Several regattas ago there was one I20 (NCSUtrey) that was started with the F18 fleet. It was more coincidence than anything else but it seemed like everytime I made a tack or a gybe to attack an F18 I was having to avoid the I20 on the course (it was certainly friendly but there was some verbal jabbing coming from my boat ). At the awards ceremony I discovered that he was being scored with us and he beat us out of 2nd place - that tid-bit of information would have changed my tactics a little and I probably would have tried to cover instead of trying to avoid getting tangled up. It was (is) all in good fun and they sailed well that weekend.