Now, people keep arguing that "except-mlist" is pointless because no
regular ISP is so well informed about its own users. But vanity domains
like mine *do have the needed intelligence*.
Not to keep beating a dead horse or anything, but I still don't see what
real life (as opposed to contrived) problem this is supposed to solve.
Bad guys have been trying to sneak unwanted messages onto mailing
lists since the era of Krazy Kevin. List managers have developed a
variety of techniques to keep the bad stuff out, and there is no
reason to think that will stop. The only utility I can see for this
hack is in a world where list managers don't do that.
Also, there are a lot of reasonable scenarios other than mailing lists
in which a legitimate message would arrive without its domain's
signature, with mail-an-article, and web mail that consolidates
multiple accounts being only two of the most familiar. Your hack
doesn't address the general issue at all.
So give it a rest, please.
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