Possible Duplicate:
Collision detection fails when saving while suggested edits are pending?
This is kind of similiar to Reject edit suggestions on old revisions, but the reverse
In this case, a user suggested an edit while the OP was already editing the post. /posts/#/edit is the same page reviewers end up when they click "Improve", and the system can't tell the difference -- when the OP submitted the edit, the engine assumed he was done improving the pending edit and Community implicitly accepted it, even though nobody had actually reviewed the suggestion and the OP's edit (based on the older revision) immediately reversed all the suggested changes
Either the OP's edit should've failed because of an existing edit suggestion, or Community should've rejected the suggestion; suggestions shouldn't get approved if nobody has read them
