How would you decide this?

Dave Perry’s 100 Best Racing Rules Quizzes highlights specific aspects of the racing rules in a fun format designed to help you become more familiar with The Racing Rules of Sailing. Here is one of the quizzes:

Quiz 93
Boat X is sailing upwind on a close-hauled course on starboard tack. Boat Y is sailing downwind by the lee on starboard tack. The boats are on a collision course. Both boats change course away from the other to avoid contact and hail, “Protest!” You are on the protest committee; how would you decide this? Answer below.

Quiz 93 Answer
Disallow both protests. Both Boats X and Y are on starboard tack as they approach each other (see the definitions Tack, Starboard or Port, and Leeward and Windward). As neither boat is clear astern of the other, the boats are “over-lapped” (see the definition Clear Astern and Clear Ahead; Overlap). Rule 11, On the Same Tack, Overlapped, requires the windward boat to keep clear of the leeward boat.

In this situation, neither boat is on the leeward side of the other; therefore neither boat is the “leeward boat” or the “windward boat.” Therefore, rule 11 does not require either boat to “keep clear” of the other boat. However, rule 14, Avoiding Contact, states: “If reasonably possible, a boat shall (a) avoid contact with another boat.” Both boats comply with rule 14(a).