Hmm. Usually with "identification by association" there should be something more consistent "associating".
The "strange surface texture" is not on all of the truss. "The Corbomite Maneuver" and "Mirror, Mirror" has some examples of some truss just solid. These surfaces are also not present in critical locations, such as the engine room or other internal rooms where you'd expect to see a whole grid of them to support the deck above (or the current deck via the ceiling.) It's the lack of this consistency that makes it difficult to prove that the truss with surface is part of the Artificial Gravity system, IMO.