I'd say that the lack of a parent domain lookup is not a showstopper,
but creates significant administrative overhead. I consider it a "very
nice to have". It certainly facilitates a world we all want to live in:
one where all of our email domains and subdomains can actually publish
a dkim=all record.
I know that there've been suggestions that new products (or features in
existing products) might emerge that would obviate the need for any such
requirement by synthesizing ADSP records at labels that don't already
have them. I suspect, however, that at many large organizations, such a
major change to core infrastructure like DNS would take as long as (and
be fraught with more political peril than) reaching consensus on any
IETF working group :).
--
Mike Markley <mike(_dot_)markley(_at_)bankofamerica(_dot_)com>
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