Thanks for the reply. Your link to w3 got mangled in adding it here. But, I found another location to explain things:
https://www.w3schools.com/htmL/html_id.asp
However, I went through all the files in the epub I'm currently looking at and none of those simple ids are referenced anywhere except where they're defined. I even searched for all occurrences of # and they were always associated with the non-simple ids in the body statements.
The only thing I can think of is that those simple ids are from the original epub (since they closely resemble the chapter names) and were used in the original TOC. But, maybe in Calibre's conversion or my playing around with editing the TOC, they got superseded with those big honkin' ids in the body statement. But, even that is odd since the id's shouldn't be defined in the anchor statements. They should just be referenced.
Anyway, thanks again.