What happened to the original opening scene to "Whom Gods Destroy"?

I remember seeing the uncut episode of "Whom Gods Destroy" (TOS, Episode 3×16) in the 1970’s which included a scene with Kirk, Spock and Scotty discussing the security question involving chess move "queen to queen level 3", at the very beginning of this episode on the Enterprise! Since then, I have never seen it again. Now, the episode starts with Kirk and Spock beaming down to the planet Elba II while Kirk is speaking his Stardate explanation of the episode.

Does anyone remember this scene, and what happened to it? It is neither on any official DVD set, original, or remastered!