Here's the bike that prompted my question. I didn't realize the ebay listing had ended:



You can see from just that picture that it's a Tommasini from 1980-85, and other parts of the bike narrow that range further. The seller claimed it was an '80s bike, so they weren't trying to deceive, and they didn't even mention the tubing type. I suppose that the original Columbus decal fell off or disintegrated, and someone replaced it with the wrong label.