How does that make any sense? If the elders know who is sending what they can give the necessary messages to the magistrates, or the magistrates can just have the titans check it out for them... though the code name idea does not sound like a bad idea either.
If the elders know who is responsible for any possible spam or slurs, they can deal with them themselves as well as file a proper complain against the guilty parties.
I never really liked how un-secretive secret societies were as far as intra-guild communications go.
