Paul Ramsey griped about this awhile ago, but I'd been holding fire
on changing it until we settled what to do about the CASE/COALESCE
issue.

Discussion: https://postgr.es/m/CACowWR0AMyUt5fwtvuDqWyYNdp-hQJj9XqSxJR6YM9sKWov=_w@mail.gmail.com