[Administrativia] Posting rules: are messages silently dropped?

Messages I send from an email address which is not subscribed to
nanog-post are apparently silently dropped. I do not receive a bounce
(like it is typically the case when a list is closed) but, according
to the archives, they are not distributed either (which may be good
for the S/N ratio but I digress).

Isn't it too harsh? <URL:http://www.nanog.org/email.html> explains how
to post but does not mention what happens to posts from