Here's one that's fresh from the racetrack. Two boats on port tack approaching the downwind mark. The first boat gybes to starboard (2) right at the edge of the zone. This kinda opens up the overlap zone. Both boats carry on and at the mark (3) Yellow yells "no room" and tries to close the gap. Blue seeks the space between the mark and yellow but fails to execute the turn and slams (4) right into yellow. Yellow protests!
Fresh from the race track
What did the jury say? What should yellow have done? What should blue have done?
PS: That Boat Scenario program is supereasy to use. If only those animated files could be made smaller.