I would also like to thank Sebastien and Andrea for this excellent paper.
I look forward to discussing in Boston the comments from Martin Hill, Patricio Ortiz, and Bob Mann.
However, I think there needs to be an additional document showing the current state of the UCD1+ tree. A printable, versioned IVOA draft document. This will force the rigour of versioning, and allow the IVOA process to control the list of words. When Sebastian and Andrea want to make changes, they should not just change it arbitrarily, but rather build a new version of the UCD Tree document and run it past the IVOA, or the UCD Steering committee, or this mailing list.
Is that too rigid and formal? Comments?
Roy