Any properly written program or correspondence should have all the answers on it. With a computer, you can't see the entire screen. This means you have to scroll around and read the entire message. Netiquette and good composition, in this case. When a flaming email goes to everyone on the list server, we all know who did it.
Humans are the most cantankerous, grouchy critters around.
Being courteous to strangers says more about you than the stranger and helps make life easier with your co-workers. It took some nerve to push the list server out like you did. If you had waited until some one told you how to do it, it would have never happened. I use a baseball analogy when I counsel Soldiers. If you take a swing and miss, the coach will let you try again.