I was watching Buzzr and a Match Game aired where Fannie Flagg had taken Brett's seat for whatever reason. That got me thinking about people who were in the "All-Seat Club" or who occupied all three seats at some point in the Match Game '7X run. This is a rare feat thanks to Brett and Charles occupying the two and three seats for nearly all the run, but a few people have done it in both sets.
In my research I found that Fannie Flagg, Loretta Swit, Patty Duke, and Gary Burghoff all accomplished this feat.
Others have also found that Dick Martin, Richard Deacon, Bill Daily, McLean Stevenson, and Nipsey Russell also count.
Does anyone know who else might have completed this cycle?