[Paul Graham on TRAPIN vs FILTER_ALSO, in re Majordomo-LISTSERV loop]
> Note: L-Soft does not recommend using  this keyword to filter out problem
> users. Rather, you should use the FILTER_ALSO keyword for that purpose.

Yeah ... but FILTER_ALSO says that it's for postings.  Have you seen
whether it stops command messages as well?  I didn't try it.

By the way, regarding Eric's post on this: I got an over 500-cycle loop
with one Majordomo system -- it was *not* served out.  The reason why,
as far as I can tell, is that Majordomo prefixes all of its messages
with a line saying "-- " (i.e. a signature begin line) as a loop control
method -- and LISTSERV ignores but quotes back all lines from there on.
So none of the Majordomo messages to LISTSERV actually generated an
error, and the auto-serve-out mechanism never got triggered.
--
  Norm

Statisticians do it both discretely and continuously.