Remove the requirement from the charter that TrackBack should try to remain backwards compatible.
Is it possible that in order to truly advance the TrackBack protocol that the group should be totally unencumbered by compatibility issues. That perhaps what we should be designing is not TrackBack 1.1 but TrackBack 2.0.
Also, this frees the group to explore more radical approaches/changes to the protocol in regards to identity, leveraging the HTTP layer more, etc.
It may also serves the purpose of expanding the protocol's scope so that it is possible to serve more than the limited number of use cases it was designed to address, and to potentially help bridge the gap between TrackBack and other related protocols.
Strike the following paragraph from the TrackBackCharter:
Although not encouraged, non-backwards-compatible changes to the basis specifications will be acceptable if the working group determines that the changes are required to meet the group's technical objectives and the group clearly documents the reasons for making them.
Backwards compatibility with previous TrackBack implementations, potential scope increase of charter of group.