Compromisiming on standalone readability by *people* is, unfortunately one of the classic premature optimisations in the XML world. The essence of XML is the yin/yang between people and machines. Tilt too far in either direction and the noosphere weeps.
The rss-data proposal tilts too far away from people in favour of machines. There is no point in teeing up a data structure for the agregations in terms of dates, strings and integers and calling it XML. It is XML is syntax only, not in spirit. If you really want to do that, use ASN.1 or something.
What is XML if it is not an aggregation of dates, strings, and integers, etc.? What is the "spirit" of XML? Is there just one "spirit" of XML that should bind us all? I really want to know more about his position.