As a result it looks as if postings to the mailing list are causing a loop
from him, since these replies are being sent to postings from the mailing
list and these in turn are generating further replies when those get sent
back to him.
You might want to temporarily drop him from the mailing list, and send a
note to him explaining why. Otherwise I'm afraid that we'll all get
innundated until he gets back.
This morning I got something like 26 email messages, 21 of which were these
robo-notes!