As promised, I have now revised the section on index entries again. You
can see the draft at http://www.tei-c.org/Drafts/CONOIX/
The main change I made (apart from stealing lots of Michael's
illustrious prose) was to add a section on transcribing existing indexes
and add some more examples.
I have not yet made but am mulling over another change: to remove
<indexSpan> and add an attribute to do the x-path-span thang to <index>
Comments, as ever, very welcome.