Not to be difficult, but messages which appear to be personal are usually
communications between strangers which are made more polite by using their
given names.  I have found that many of the questions and answers are of
interest to me, even though they had no immediate application to my work.
Such queries are also the way threads seem to get started.  But the
answers can provide some terrific information, information which I can
enjoy without sending an additional message along the lines of "Hey, I'm
just curious. Could anyone reply to me off list if they have an answer?."
In short, if someone has a query, and I, for instance, answer, I cannot be
sure that others on the list would not be interested in the subject.  At
least I know that at least one person is interested in my brief response;
unlike with some long, unsolicited posts.
 
Finally, you will notice that there is an "Reply to" address in the
message heading.  If one uses the automatic reply function to answer a
post, it will normally go to the whole list.  Thus, sometimes people will
inadvertantly post to the list a personal message.  On the other hand, one
cannot be sure that the original sender did not, in fact, want replies to
go to the list.
 
Speaking only for myself, I don't see any problem with many of the
answers complained of.  If it's strictly personal, then keep it off the
list.  If it's not, it's probably nice to keep it brief--probably briefer
than my above message.
 
Tim Dennee