I'm sorry folks but I gotta get my sailing fix for the day. This question came up recently, names are witheld to protect the innocent.
Two boats on starboard tack. A F16 is finishing downwind (under spinnaker). Can he legally head up, preventing an A cat (or any other type) from finishing. By heading up he will sail faster and improve his portsmouth score, so he is not sailing above proper course.
I say this is one of those execptions. He must allow the other boat to finish.
The finish is a mark of the course. If he has overlap you have to provide him room to round it.
In the case where the line is closed and in the middle of the course, it is an obstruction and you have to provide room for the other boat to avoid it.
