Short, concise description of the idea
How about giving the owner of the journal page the option of allowing or not allowing cross-posting of comments by readers?
Full description of the idea
You say you want to protect privacy and you can't control reader behavior. But you CAN let journal owners protect their privacy by controlling reader behavior in this case. People on LJ use screen names so they aren't broadcasting their identity to the world, like people do on Facebook. Making a journal "friends only" restricts readership. LJ authors often don't want to restrict readership. They just don't want the whole world to be able to connect the dots between their LJ screen name and their Facebook name. Commenters are choosing to reveal the connection between their LJ identity and their Facebook identity. Commenters shouldn't be able to choose to do that to/for other people besides themselves. A little bit of triangulation will connect dots that LJ page owners may not want to be connected. So let the LJ page owner control whether commenters can cross-post comments.
- Open journals stay open instead of being converted to "friends only". Continued circulation of ideas without worries about identity being revealed.
- No need for journal owners to post requests that readers refrain from cross-posting. The journal owner controls it. Peace of mind for the journal page owner; continued usage of LJ.
- The "no cross-posting" option might have to apply to the entire journal, not customizable for each entry.
- Commenters might not get to splash every last jot and tittle of their private lives all over their walls. But they will be prevented from splashing somebody else's private life all over their walls.