You definitely gotta have a rule book Matt!
The Fundemental Rule says " When boats are on opposite tacks, a port tack boat SHALL keep clear of a starboard tack boat.
In this there is no ambiguity, it is simple cut and dried, The starboard tack boat does have rights (all of them), but iaw with international rules for All vessels it is still the responsibility of both to avoid a collision.
This is dangerous talk, because it is simply not true. Starboard does NOT always have all the rights over Port. This is very important.
Rule 18 is one of those that "limit the actions of a right-of-way boat".
Rule 18 does apply to two boats approaching a downwind or gybe mark on opposite tacks. Outside the 3-boat zone, port gives way to starboard. Inside the 3-boat zone, if the boats are overlapped when the leading boat reaches the zone the outside boat must give the inside boat mark room - port/starboard is not an issue.
This is very important at a starboard-hand leeward mark where a boat on starboard must give way to one on port as the one on port will be the inside boat.
