Situation
Blue was overlapped to windward and inside Yellow when the first of them reached the zone of a leeward mark. Blue intended to leave the mark on port tack, while Yellow intended to leave the mark on starboard tack. While rounding, Yellow luffed to head to wind. Blue was able to respond in a seamanlike way. Blue passed head to wind and left the mark on starboard tack. Yellow then did the same. Blue protested Yellow for not giving mark-room.

Question
How should the protest committee decide the protest?

Answer
The protest should be dismissed because no rule was broken. 
Yellow was required to give Blue mark-room under rule 18.2(a)(1), and she did so since she gave Blue room 
(a) to sail to the mark (as the proper course for Blue was to sail close to the mark), 
(b) to round the mark on the required side, and 
(c) to leave the mark astern. 
In addition, Yellow gave Blue room to luff until head to wind when she changed course and complied with rule 16.1. Blue kept clear of Yellow as required by rule 11.