The problem I have with this argument is that blackhole lists, in my
experience, cause a large number of legitimate messages to fail to be
Having gone to a lot of MAAWG meetings, and talked to people who run
the mail systems at every large ISP in the country, and quite a few in
other countries, I can report that their experience with DNSBLs is
utterly unlike yours. There are plenty of incompetently run DNSBLs,
but nobody uses them so they don't matter.
I have my reservations about the wisdom or utility of providing fine
grained reports to people whose mail you don't accept, but not because
of error rates in DNSBLs.