Huh this is news to me. My field guides all mention the color variation but don’t mention differing behavior. One guide even incorrectly says its based on age (it is worth noting they do vary in plumage depending on age, but in a different way).

Another bird that is sort of like how they describe in the article is the Ruff. It is a beautiful type of sandpiper where males are split into 3 categories with different appearance and behavior.