dynamically list related posts
You can dynamically show similar posts (as in ecommerce sites), selected by <cms:pages> after some criteria (for example, same author or editable field has certain content). What I mean here doesn't require establishing a "relation" editable.
Alternatively, once you have a list of desired posts that match your criteria, it is possible to get their IDs. In case you do have a "relation" editable, it is possible to auto-assign known ids to a post. Such operation can be performed by <cms:db_persist /> tag.