Interesting question and a nice idea. whistle
Imagine what happens when the crewmember rolls in the jib just before the last windward mark, hoists the spinnaker and then jumps overboard allowing a fast last downwind run for the skipper grin
regards, Michael
Your comment seemed like a joke but just to clarify...
RRS 2009-2012, p24
47.2 No person on board shall intentionally leave, except when ill or injured, or to help a person or vessel in danger, or to swim. A person leaving the boat by accident or to swim shall be back on board before the boat continues in the race.