...CBS has dismissed calls for an internal investigation into its reporting of the story, arguing that it was thoroughly reviewed before broadcast. "I'm confident in the process of vetting that got the story on air. When we say we continue to report the story you can be sure we're being conscientious in responding to these allegations," says CBS News President Andrew Heyward. CBS may offer further evidence in support of its story as early as today. The stakes are high for "60 Minutes," the undisputed gold standard in television news.... Its longtime producer, Don Hewitt, 81, has retired unenthusiastically, and...