It is my belief that most recipient domains are likely to find not
checking author domain SSP (for discardable) as an invitation to
abuse.
It's hard to see this as saying anything other than that SSP
publishers get to regulate the operation of mailing lists,
send-an-article, etc. run by unrelated third parties.
Even if it's against my internal rules for one of my users to
contribute to a mailing list to which you subscribe, I can't imagine
how I could expect that you enforce my rules against my users.
Or to put it more baldly, it's not mail abuse just because I don't
like it.
R's,
John
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