NEWSFLASH: Talk show hosts read jokes written by others off teleprompters!
Ever watch the closing credits of a TV show, Oprah, Letterman, Dr Whoever, etc? Seen the names of “writers”, sometimes a dozen or more? What do you think those writers wrote, the closing credits that list their names? Duh!
Those “jokes” are approved by the host, the director, producer and network brass. BTW, Letterman and O’Brian both still help write much of their own material.