[quote name=\'DoorNumberFour\' post=\'170079\' date=\'Nov 20 2007, 06:29 AM\']
But now that I'm fully rested:
Bud Collyer, Robert Q. Lewis, Merv Griffin, Gene Rayburn, Ralph Bellamy, Sonny Fox, Jim Fleming, Bill Cullen, Orson Bean, Mark Goodson, Bert Convy, Garry Moore, Joe Garagiola, Robin Ward, Gordon Elliott, Alex Trebek, Lynn Swann, John O' Hurley.[/quote]
Technically, Alfonzo was originally talking only about the original version of Concentration, so I was limiting my names to only the original version of TTTT. But if we're going all-in, I think Richard Kline absolutely counts - a show that aired by mistake still aired. Also keep in mind that Peggy Cass and Kitty Carlisle each sat in the host's chair for a single game, in both instances because it was known in advance that they knew the central subject.