Now, the question is... Could I have called for room to tack? assuming the course change I had to make was "substantial" enough to pass below the anchored boat.
Well, the term "substantial" is not defined in the rules, so this is a bit of a gray area. If all you have to do is foot off a little to safely pass an obstruction, then I'd typically rule that your course change was not substantial. In that case, rule 20.3 denies you room to tack. You must duck instead. Rule 19 requires you to give an overlapped boat room to avoid the obstruction as well.
I hope that helps,
Eric
US Sailing Certified Judge
Member, Area D Appeals Committee
