Nevertheless, procmail doesn't seem like the right answer.
Perhaps not for all.
But the other extreme (which some here regularly advocate) is complete
openness to all - just in case they might potentially have something
useful to contribute - even if the overwhelming past history strongly
suggests that will never happen.
We have people that post that are effectively DOS generators. Their
postings are largely not taken seriously (or even read most likely) by
anyone who has been an IETF contributer for any length of time. Yet
they do get responded to (even the strong sometimes have moments of
weakness and take the bait) and it sucks away cycles from the
community that should really be directed towards more important
things.
Yet, by not kicking them off of lists and otherwise making it clear
that they have worn out their welcome, the community sends an implicit
signal to the lurkers/newcomers that even such voices are welcome and
that their disruptive tactics are perfectly acceptable behavior. Even
worse, it probably encourages some do to do the same.
Of course, everyone should get a grace period when they start, but it
should not be open ended. IMO, we are sometimes too tolerant of what
should be unnacceptable behavior -- behavior that is a drain on IETF
resources and produces little of use in return. IMO, it does not help
the organization and it even drives away participation from those we
really want to keep.
Case in point: there are many long-time IETFers who do not subscribe
to this list. Signal-to-noise is just too low. That should tell us
something.
Thomas