I don’t think this is a great comparison. Since I’m American, I’m going to pick something else that would be a bit more foreign: I can “tell” if a person is Scottish or Irish from their accent, but I have absolutely no idea how to know if someone is of a certain caste. I could meet up with a carbon copy of myself and not be able to discern their caste because I have zero knowledge of why I “look like” the one I belong to.