This is kind of a spin off of the "Performer vs. Showman" thread. I'm interested in people's opinions of what works and what doesn't when playing to an audience. I've got my own opinions but I'd like to hear what others think - what they view as disasters or disappointments and what they view as successfull. I've certainly noticed that many mediocre or "okay" performers are successful because they know how to play to an audience. Is this a learned skill, or do you either have it or not?