Reminds me of the British sailor who thought his sail touched a mark in a race at the Olympics. He was so far ahead no one else could have seen it. This was before you were allowed to do turns to exonerate a rule breach. He withdrew. Your competitor is obviously not of this caliber. If "he won the series even if he was chucked from that race" he has even LESS reason to not do turns: it doesn't cost him anything to do them. Not following the rules here brings up the question as to whether he followed the rules when he "won" his dinghy titles, and at other times as well. Elvstrom is right.
The sailor was american, not British. It happend in the Finn class.