"(Semler's ideas have) sort of seeped into the establishment, " says Tom Stewart of the Harvard Business Review.

CNN: Democracy in the workplace

Past guests have included Walter Cronkite, Tom Brokaw, Jon Stewart and even George Clooney.

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That means the Sunday "golden oldie" slot - previously taken by the likes of Rod Stewart, Tom Jones and Tony Bennett - will be vacant after organisers said they could not afford Bryan Ferry.

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