The zero-width spaces were a minor inconvenience when I was copying &
pasting macro names out of the table into source code ... not a big
inconvenience though (my editor showed them as some non-printable character
so I saw them right away).

I think splitting the tables from the examples and rationale makes sense,
but I don't feel strongly about it. As for having SD-6 be two documents,
the actual recommendations would be in the tables, so that would be SD-6.
The rationale would be a separate document, call it SD-7 (if that's not
taken) or just "SD-6 rationale", but I don't see that being a big blocker.