I wonder if it would be usefull to add an optional destruct-code in the PM aswell? This way, you could send a first PM with a destruct code, if a deal falls trough the PM gets published... But if the deal goes fine, the initial sender can send a PM with the destruct code and the initial PM will be erased instead of published?
It can't be just the sender deciding on this: the receiver can require evidence too.
I thought of adding a command like "remove=10925297", but it has to be confirmed by the sender and all receivers. However, if a potential scam victim receives the PM as BCC, I can't know they need to confirm it too. So I decided to abandon this idea unless a better solution comes up.