One noteworthy thing about Mr. Terrific is that it didn't do badly during its brief run on CBS in the ratings. If you look at the 1966-67 ratings list (compiled by AC Nielsen for all 90 shows that year), Mr. Terrific ranked a healthy 36th - ahead of The Invaders (39) F Troop (40), UNCLE (42)...
Stephen Strimpell gave an interview to Filmfax (or Outre) magazine around 2001, a really candid chat about how much he disliked working on the Mr. Terrific show but he was also very funny, a great wit. He died a few years ago.