In my opinion they were never subtle.

It makes me recall my high school text books, specifically my science books, where in the parts of the book filled with experiments to try at school there was always pictures of "students" in the book trying it too. It was always 1 white, 1 black, 1 Asian, 1 Hispanic, and 1 in a wheelchair of some random race (ALWAYS there was a wheelchair kid), and at least half or more were female, usually more. Me and the other kids in class would always call the wheelchair kid "Wheels."