However the angle bracket stuff is what most mail administrators will
find themselves staring at when debugging mail deliverability
problems.
That's my main reason for prefering SPF syntax; I just find it easier
to read (visually less cluttered) than XML, and its simpler (less
flexible) syntax is easier to parse visually, precisely because of the
lack of nested structure.
Am I overestimating the extent to which MARID records will end up
being written and read by hand by mail admins...?
Take a look at the records being discussed on this list. I don't
have a clue what they mean unless I sit with the spec and work them
out, I just don't.
Sure they might look intuitive if you think that "ps -aux" is a
model of clarity in command line syntax, but even a UNIX sysadmin
can't say what the effect of that command is without knowing
which version of UNIX is running.