Norm Macdonald delivering his final emotional goodbye on David Letterman's show is heartbreaking, and honestly I would simply tear up every single time if I had to say goodbye to an icon like that.Norm Macdonald: Listen folks, this will be my last time on the David Letterman show. Norm Macdonald: We all know that David Letterman was the greatest talk show host who ever lived.Norm Macdonald: Mr. Letterman, he has no truck for the sentimental, but if something is true it is not sentimental, and I