I don't quite understand your reasoning. If our Lord decrees that uncontrolled duels are prohibited, then those who challenge without permission are clearly disloyal towards our Lord and should be forced to commit seppuku. The goal of everyone here is to survive, even for the traitors among us and challenging without permission of our Lord is in conflict with that goal as it would bring a lot of suspicion on the challenger, so if we do enforce it with lynching the culprit, uncontrolled duels will end very quickly.
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