Yes, and another disadvantage to nonexplicit thumbnails is that the thumbnails would always have to be manually screened.
If the US TGP owner goes to text-only gallery links, the TGP gets the advantange of a keyword rich page which will bring more search engine hits. Also, a text-only gallery links may have a better conversion ratio. One of the US TGP owners who converted from a thumbnail to a text TGP found this to be true.