I posted this quiz to highlight a change in the rules. If you were not aware 17.2 is deleted in the new rules. This rule didn’t allow yellow to sail below her proper course. Therefore, under the old rules at both position 2 and position 5 yellow would have broken old rule 17.2. As I think this scenario demonstrates this rule is completely unnecessary. There are plenty of rules to protect the leeward/clear astern boat on a run. I can honestly say I routinely ignored 17.2 coming into a leeward mark when trying to make sure there was no overlap at the zone.As for the correct answer all were correct that Yellow should be DSQ. I think the writers of the question failed to give us an important piece of information. Was there an overlap established when yellow turned down between positions 4 and 5? Since the question did not indicate an overlap, I would say technically the correct answer is Yellow breaks Rule 16.1, and Blue breaks Rule 12 and is exonerated. However, practically looking at the diagram it is hard to see how yellow can turn down as she did and not create an overlap. So a Rule 11 violation for Yellow and 16.1 for Blue with Blue being exonerated, is also a reasonable answer. Either way Yellow is DSQ and Blue is exonerated.