Explicitly say that there isn't a defined model for combining multiple Atom Feed Documents into an information feed.
Newly proposed; follow-on to PaceFeedState.
One of the most prevalent use cases for RSS and Atom is to maintain a store of past entries that have been seen, so that new entries serve to update them. Doing so requires a specific state model to account for how entries and feed metadata are updated, how to recognize missing entries, etc. If the WG does not provide an explicit way to do this, we should say so.
=== x. Managing Feed State === Atom Processors MAY keep state (e.g., metadata in atom:head, entries) sourced from Atom Feed Documents and combine them with other Atom Feed Documents, in order to facilitate a contiguous view of the contents of the feed. The manner in which Atom Feed Documents are combined in order to reconstruct a feed (e.g., updating entries and metadata, dealing with missing entries) is out of the scope of this specification, but may be defined by an extension to Atom.
Fills in the long-empty section "Managing Feed State" in the format draft.