(Just to be clear: by Austrian, I'm talking about the school. It's possible that economists who live near Germany are also stupid, but that's not what I'm talking about.)
From what I can see, the logic is:
1. Follow a theory to its logical conclusion. Eg. "All government actions are bad + "socialist" (ie "government does things") governments provide healthcare" -> "Nobody has access to healthcare in socialist countries", "No healthcare -> people die early", "If people die early, there are no old people!"
2. Assert logical conclusion as fact, without checking. "Yeah, well of course Britain doesn't have a pension problem, everyone dies before the age of 30 in that country!"
3. When others assert "WTF", come up with logical process rather than facts. "Uh, hello. Britain has socialist healthcare! Nobody in Britain can possibly live long enough to reach the age of 30, given they all die of preventable diseases!"
4. Simply ignore statements to the contrary. "No, Britain's socialist healthcare system means everyone dies before the age of 30. And Keynesianism is totally discredited."