It appears that Sam Varshavchik <mrsam(_at_)courier-mta(_dot_)com> said:
MXes which do not announce their limits are going to dominate for some time.
So, I still need to do this for the foreseeable time. So, what does this
SMTP extension buy me? The only thing I can think of: not duplicating
messages when I don't need to.
But the thing is: I don't recall anyone raising this to me, as a problem.
This is not on my radar screen as a problem that wants to be solved.
I wouldn't think that your users would be very interested, but bulk mailers are
any hints about how much mail they can stuff at people without getting blocked
or rate limited.
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