Forwarded messages from other Lists containing jokes and other unrelated material are discouraged. Many members pay real money to download posts, and they don't appreciate paying to get David Letterman's Top Ten List. In this fashion, those members who like getting medically related jokes or your personal spin on some subject can view them and those hard noses that have no interest in such fluff can delete them without looking. Try to keep your messages short and to the point. Compose your message and spell check it, then go over it one more time to see if you can cut out any fat.
Many members are on more than one list and they have a limited time to read posts.
If it is too long may be deleted on first sight as soon as it's length becomes apparent. If I think a thread is starting to drag, I might contact the principals and request they continue individually. Have something to say or to add before you post. Messages offering thanks, jibes, or congratulations need only be mailed to the interested parties. By the time most people receive such items, they will long since have been informed by conventional media.