[just thinking out loud... it has been a while since my cs masters days]
One problem with "post many/edit one/update all" systems is that it is possible (not likely with smart users, but still possible) that the one of dependent journal entries could be changed and those changes lost when the master entry is updated.
For example, simpleuser allows her friends to tag her entries over on LJ. She posts on Dreamwidth, crossposts, and thinks nothing of it. Friends read, tag the entry, and move on. Later on, simpleuser realizes she has a typo and edits her entry. She notices she didn't tag the entry on Dreamwidth and does that too. She updates and then...
What should happen to the tags over on LJ? If the client plays nicely, then they should be preserved... but are the new tags added as well? Should they overwrite? Should the LJ tags be pulled in and merged? Granted, simpleuser could not allow her friends to tag the entries, but the point is more to illustrate how easy it could be for the entries to get out of sync.
If there is a simple policy: "Dreamwidth always overwrites" that works, just needs to be made known up front.
Musing about editing cross posts
One problem with "post many/edit one/update all" systems is that it is possible (not likely with smart users, but still possible) that the one of dependent journal entries could be changed and those changes lost when the master entry is updated.
For example, simpleuser allows her friends to tag her entries over on LJ. She posts on Dreamwidth, crossposts, and thinks nothing of it. Friends read, tag the entry, and move on. Later on, simpleuser realizes she has a typo and edits her entry. She notices she didn't tag the entry on Dreamwidth and does that too. She updates and then...
What should happen to the tags over on LJ? If the client plays nicely, then they should be preserved... but are the new tags added as well? Should they overwrite? Should the LJ tags be pulled in and merged? Granted, simpleuser could not allow her friends to tag the entries, but the point is more to illustrate how easy it could be for the entries to get out of sync.
If there is a simple policy: "Dreamwidth always overwrites" that works, just needs to be made known up front.