It's his server. He gets to decide how it responds when people send it requests. If there's a disconnect, I think it's the people telling jwz how he needs to configure his server.
Sending drastically different content based on where your URL was clicked from, should indeed count as one definition of "not understanding how the hypertext web works." It's also something you're free to do, and the rest of the web is free to stop linking to you in response.
I don't understand why you think this contradicts anything I said.