Excerpted from Curtis Kam's
Wrestling with Magic :
Thank you, thank you, thank you, for whatever attention you'll dedicate to these random thoughts about magic. In consideration for your indulgence, I've tried to reduce things into those pithy little sayings that we all have floating around in our heads. I love those things. They sound wise and true, and they're easy to remember when you're drinking. Not all of these are mine, but they’ve all been useful. You are welcome to challenge my thinking on any of this, since your own experience trumps any theory. In fact, that's the first “rule”.
~ Experience Trumps Theory ~
Magicians juggle a lot of theories. “Never challenge the audience,” they say, but have you ever seen Slydini? “Magicians stop thinking too soon,” we're told, but aren't “90% of all tricks ruined by improvements?” Less is more, more or less, and therein lies the rub. How much is too much, and when is enough enough? Theories are just speculation without data. And in magic, that means experience. Henning Nelms said it best:
You are preparing a routine for the public, and the public contains a large percentage of fools. The only way to gauge audience reactions in advance is to find out how laymen actually react. If you are concocting a new dog food, the opinion of a battery of French chefs is worthless – you must try it on a jury of dogs. Magic and Showmanship, p. 18 (1969)
For example, theory tells us that a natural move avoids attention. On the other hand, a retention of vision pass is a convincing illusion, but only when the audience is paying attention to the transfer. So do you call attention to a retention pass, or not?
Here's how a “jury of dogs” settled that one for me: I was goofing around with a bunch of kids and performed a retention pass, apparently dropping a coin into my right hand. They followed the illusion and stared at the right hand. When the coin disappeared, they grabbed that hand, and looked it over, front and back. Then they went up into the right sleeve, then my jacket pocket, and moved for my pant pockets. They did not even consider the “other hand”. If the task was to convince the audience that the coin was where it wasn't, I figure that worked.
That's certainly not enough to settle the matter, but it's a data point one that's not just a general feeling that nobody saw anything. Gather enough of these, in front of enough audiences, over enough years, and you start to see patterns. That's not to say the audience is always right. You've got to ask the right questions. A lot of theory is just rationalization. Be suspicious of any theory that tells you to do less, to know less, or be less.