I spend a lot of my time reading books and listening to tapes about business and marketing. I guess that's understandable.Many of the authors of these materials are known as experts, gurus or marketing geniuses. However, a few weeks ago I was listening to a discussion about marketing and one of the participants made a point that struck me like a ton of bricks.He said: "The only true marketing genius is the customer".What a succinct and powerful statement!The truth of the matter is that no matt.