John Ratzenberger pitched his 'know-it-all' 'Cheers' character, mailman Cliff Clavin, to the show's creators on the spot at his audition, he revealed to costars Ted Danson and Woody Harrelson on their podcast 'Where Everybody Knows Your Name.'
https://people.com/john-ratzenberger-created-his-cheers-character-durin…