Well, if you go Split Second, you have to go with the 1980s Hollywood Squares round too...same principle.
The Split Second Bonus Game may not be related to the main game, but it was fun. If you haven't seen the Robb Weller pilot for the Split Second revival, be grateful... that bonus game, also based on luck, had NONE of the excitement of the Kennedy or later Hall version.
While we're on Squares, the Big Money Round is on the list too- totally out of place.
Few others: The Turnabout Round on Child's Play- the whole point of the game was to guess how kids defined words, right? Why change it?
It was either changed because the original format was too hard or too easy. Also, it's possible that they felt the children should be featured more and allow Bill to play Art Linkletter to get more "gems" out of them.
The Big Numbers Round on Las Vegas Gambit- call me crazy, but why are you going to bring dice to a game based on blackjack if you really don't need to? Casino theme notwithstanding?
The original bonus game was a "live deck" of cards. Audience members represented cards, and it was identical to the original Gambit bonus game. I suppose that didn't work out and not having a better bonus game, just played the High Rollers bonus game instead.