As a philosopher, you're trained to pick apart arguments and spot their logical errors. To point those out, you use various techniques, one of my favorite of which is to construct an argument making the same error but where the error will be more easily spotted. So, when I saw this:
"Tyler Cowen is not an authority on Austrian economics because (hey, guess what!) he's NOT an Austrian economist."
over at The Curious Capitalist, I was tempted to post something like, "So, famed astronomer X cannot be an expert on flat-earth theory because he's not a flat-earth theorist?"
But then I stopped, because I knew I'd get two main reactions:
"Ah, so Callahan says Cowen is an authority an Austrian economics," or
"Ah, so Callahan admits Austrian economics is like flat-earth theories!"
Now, no trained philosopher would ever read my argument that way. She would know that the analogy is between the argument forms, not between Cowen and X or Austrians and flat earthers. But, man oh man, I've had dozens of similar arguments misread by casual blog commentators!