This dates me, there is no physical evidence to support my claims, and no one has mentioned this but...
Let's Play Post Office: I was only nine years old when this aired after some other quiz game that Merv Griffin developed so I didn't know the names of most of the people who were the subjects but I enjoyed playing along. I admired the style of eschewing buzzers and having the players scream, "Stop!" when they are ready to record their answers.