To see why the revised Rule 21 is a fairer rule, consider the common situation shown in Diagram A, which shows Tom and Jerry sailing on a run, spinnakers set. Tom overtook Jerry from clear astern, so Jerry may sail above his proper course (see Rule 17). Jerry luffs Tom so rapidly that even though Tom responds promptly and does all he can in a seamanlike way to avoid contact, Tom’s spinnaker touches Jerry’s windward shroud at Position 2. There’s no damage, and neither boat takes a penalty. Tom protests, alleging that Jerry’s rapid luff broke Rule 16.1 by not giving him room to keep clear.