My favorite example of that is TNG S3 - " Who Watches The Watchers", where they refer to the Mintakins as " Early Proto-Vulcans" <-- however these said "Proto-Vulcans" are logical and peaceful, and most seem to have their emotions in check or very subdued...
Early Vulcans logical and peaceful with a hint of emotional control?
Whomever wrote the episode didn't really watch the original Star Trek much did they? But, back in the day I didn't see the TNG writing or production staff raked over the coals for this one, even though it clearly showed they had no knowledge of Star Trek Canon or Continuity when it came to the Vulcan civilization.
I always figured they meant biologically similar.
