Nearly a nit, but not quite.
Some of the text here should be moved to the overview document, but
I'm not sure when's the best time to do that though. Not until
after we've an overview-00 done, maybe. In particular the appendices
look ripe to be moved.
Also - the order of presentation makes base hard to read for me at
least. If one of the introductory sections had a fairly well worked
example and provided quick informal (non-normative) descriptions of
typical uses of the main fields then I think that'd help the reader.
As it is there are a lot of forward references within the document
that make it harder to follow.
S.
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