At the time Keeler mentioned Gable to Kirk, he was considered a bit player. It was not until 1932 that he performed a role that garnered him any significant recognition. This, however, may indicate a point where Star Trek history varies from our reality.
During his long film career, Gable worked together with a number of Star Trek performers and production staff members. Most notably, he starred in the 1958 film Run Silent, Run Deep directed by Star Trek: The Motion Picture director Robert Wise. Also, his best known film, 1939's Gone With the Wind was photographed by Ernest Haller and featured Phyllis Douglas.