Okay, took a few minutes to fix the Pie^WEcho^WAtom feed.
The glaring mistake was not wrapping the markup for each entries’ content in a div. Thus the validator at http://feeds.archive.org/ was rejecting every entry in the feed. I also needed to add ‘Z’ to end of the GMT date strings.
One problem I have is that there are 2,700+ entries that use YYYY-MM-DD as sole date stamp. Converting those to GMT from Local is not going to be accurate, but as Bill Kerney points out, I should be basing everything off of GMT.
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