But did the Starboard tack boat hail the port tack boat? In some instances the starboard tack boat would rather duck the port and hope the port doesn't tack, he might not hail, and choose instead to duck. Unless he hailed "starboard" or after the duck, hailed "Protest", if I were the port boat, I don't think I would consider him fouled at all. Maybe he didn't want to exert his rights and ducked instead so as to keep clear air? Is that considered a "Foul" by the port tack boat?

I know I have often ducked port tack boats because I wanted to continue on, alone. But if I don't want them to tack I either hail them that I will duck or try to duck early enough that they don't tack on me.