A port-tack boat yelled 'Starboard!' to bluff me off — is that allowed?

No — it breaks two rules. The boat hailing was on port and still had to keep clear under Rule 10, and deliberately deceiving a competitor with a false hail is not fair sailing, so it also breaks Rule 2 — which carries disqualification and can trigger a Rule 69 misconduct hearing. (World Sailing Case 47.)

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<iframe width="560" height="315" src="https://www.youtube.com/embed/9BGL6CfzG1I" title="Sailing Kiwi" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
<p><a href="https://sailing.kiwi.nz/v/9BGL6CfzG1I/">Source: Sailing Kiwi</a></p>

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