Tim,
Most list software does seem to "recommend" replies going to the sender
and not back to the list. I always thought that was a funny position...
it sort of acts to squelch discussion. Sometimes people post replies to
the list that they meant to be private (everyone who's done that,
please raise your hand) but those usually aren't too serious. The more
serious, the less likely the act will be repeated. :) I think the
mistakes are worth the improved discussion flow.
I think it's much, much better if the e-mail addresses in the archives
are not available to harvesters. Big, centralized list servers are
attractive targets for harvesters, and we know Xmission's are scanned.
I already get spam at a sustained rate of 50-100 per day; while I have
taken steps to deal with the torrent, not everyone has the same options
I do.
For the lists that I manage, I have messages from non-senders sent to
me for approval. Every once in a while these messages are spam, but the
list software I use filters out messages which aren't To: the list, and
that takes care of almost all the spam. If you're getting fifty spams
in just a few days, I think it's reasonable to just turn off the
forwarding, and have list members contact you if they're having trouble
posting.
--Damien