The boat that touched no one got disqualified — how?

When a right-of-way (starboard) boat is an obstruction, Rule 19.2(b) makes the outside overlapped boat give the inside boat room to pass it. Refuse, and the inside boat — denied her room — is exonerated under Rule 43.1(b), while the outside boat that never made contact is the one penalised, under Rule 19.2(b) and Rule 14.

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<iframe width="560" height="315" src="https://www.youtube.com/embed/PfFKsMq9lhY" 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/PfFKsMq9lhY/">Source: Sailing Kiwi</a></p>

Next on this shelf — The Upwind Beat