One of the most egregious mispronunciation errors in Trek is in TAS: The Pirates of Orion, in which Orion is pronounced OR-ee-on instead of or-RYE-on.
In "The Corbomite Maneuver," Balok says his own name as "Bay-lock," but Dr. McCoy pronounces it to rhyme with "phallic." Almost as if he'd never heard the name spoken before, but only seen it in print . . . like in a shooting script or something.
Mr. Laser Beam wrote:
Perhaps their real names ARE John and Mary, but they are so old that they have forgotten how to spell them? Use of language does tend to drift over time, perhaps this extends to people's names as well.
Not to mention the United States Constitution!