Complacent Gaming Syndrome: During the Stunt era, the number of seconds earned per correct answer was 5-10-20-40-80-100, which basically encouraged couples to not solve the puzzle if they knew it early on and rewarded those who couldn't figure out the solution early.
On the other hand, Kline & Friends probably didn't expect anybody to get the maximum possible Prize Vault time of 765 secondsnote (one couple answers all six questions correctly in all three rounds for 255 seconds each, but their opponents win one of the first two puzzles), since then the Prize Vault would last over twelve minutes and the entire show would be subject to extreme editing.
Inverted when the Prize Vault rules were slightly changed to stop the clock while Rayburn/Farago described the chosen stunt.
Subverted with the introduction of the Master Puzzle format in January 1986 (which also altered the main game to reaching a goal of $2,000). As hinted at above, Farago's first few weeks used the Stunt format.
WTH, Casting Agency?: If you wanted a serious host in a silly stunt-based game, then why did you hire a guy known for his spontaneity and who essentially built his career through being a goofball when he could?
Gene wasn't always a goofball, of course — when time came for contestants to go for the big money, he toned down the joking just enough so that all present could concentrate on what was at stake. On this show, Gene got semi-serious once the Bank Cards were being tabulated.