You said, "Nevertheless, they are not synonyms, and the existence of these two different words suggests that there is a useful distinction, even if it is not sh

You said, "Nevertheless, they are not synonyms, and the existence of these two different words suggests that there is a useful distinction, even if it is not sharp, and even if it is not always applied consistently." That is what I was responding to. There is a difference, but it's social and not linguistic. Which means when you say things like, "Chicagoese is clearly English", that you are making a social judgement that they are the same language, whatever that means to you. Clearly, for at least a few people quoted in the article, it has social meaning that they both speak "Chicagoese" and not "just English". So they might have a quite different opinion on the matter. And clearly the author of the article does.