Well, having just tried to find out which user of a list was
"bouncing" (since I had received several), I realized that
the user had been automagically unsubscribed, but I hadn't
gotten to that.  Thus, I spent all sorts of time looking
for that user both on the list, as well as analyzing mailer
tables and re-direction via auto-forward.
 
The reason for multiple bounces was that the list's high-volume
mail was in-distribute before the first bounce was able to be
processed by the auto-delete logic of LISTSERV.
 
I'm sure there is a moral to this story ;-)
 
/Pete