well, now I'm completely confused. to my eyes, your example fits
exactly what 'registered' and 'resolvable' mean, but I guess you
have something else in mind.
Steve is quite right. Since the DKIM key records are at different
names from the related MX or A record, the existence of one doesn't
require or imply the existence of the other.
I don't want to hold up this errata/update/whatever any more than it
already is, so I'd suggest taking out any wording about the DNS status
of the SDID.
One of us should send in a separate technical erratum saying that DKIM
key records SHOULD be published only for SDID domains that have
corresponding MX or A records and can receive mail.
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