There are good reasons for including the second part of Rule 18.1(b). It is intended to cover two situations. They are shown in the first two diagrams. Suppose Pete, on port tack, and Sally, on starboard, are on converging courses approaching a windward mark to be left to port. Sally is clearly fetching the mark and, in fact, is close-reaching to it because she has overstood. The first part of Rule 18.1(b) states that Rule 18 "does not apply while . . . boats are on opposite tacks. . . on a beat to windward." The term "beat to windward" is not defined in the rules, but in nautical dictionaries, it is defined as "to sail closehauled or above." Sally is sailing below a closehauled course, and therefore, if we did not include Rule 18.1's second part, Pete would be able to ask for room from Sally. However, because the proper course for just one of the boats (Pete) is to tack, Rule 18.1's second part implies that Rule 18 does not apply, and so Pete must keep clear of Sally under Rule 10.