In the Card Player magazine (July 14, 2009, casino version), shown in the scan above, John Vorhaus gives what he calls wisdomettes. Here's one:
Don't bite the hand that feeds you.
If you're beating up on some weakie, and
he's giving you all his money, don't do
anything to distract him from his task.
Especially don't berate him when he draws
out on you. He has to draw out every once
in a while in order to maintain his
enthusiasm for the game. Don't begrudge
him his wins -- they're only temporary.