In a multi-fleet dinghy regatta, the SIs state that “after the first warning of the day the Start/Finish lines are restricted unless preparing to start, starting or finishing.” No mention is made of any areas designated as obstructions.
After starting but before finishing, Boat A and Boat B are sailing downwind towards the start/finish pin, an inflatable tetrahedron. As the boats approach the pin, both boats are on port tack with Boat A overlapped to leeward of Boat B.
Boat B, the windward boat, is on a collision course with the pin. When they are two boatlengths away, B hails for mark-room. Boat A luffs slowly in response. As a result of her luff, Boat B is forced to sail to windward of the pin and over the line in order to avoid a collision.
Part 1. Is Boat B entitled to mark-room?
Part 2. If your answer to Part 1 is yes, is Boat B exonerated for sailing through the start/finish line?