Shrier mentions The German Stare a few times. And it strikes a nerve with me because I know that stare. It's the stare you get when you disagree with a strongly held "opinion".

What I think is happening:

Holding an "opinion" about something for which evidence is, say, not good takes actual effort. You may not even be able to imagine putting "effort" into an opinion, but that is because your opinions are weak!

In the sociological realm everything is floppy and subject to endless sculpting, but some things are beyond the pale. "Bring back infanticide!" etc.

If you happen to hold an "opinion" that is somehow flagging in objective ways then you might find yourself getting desperate for strategies to keep the eternal flame of "opinion" burning strong.

One strategy would be to try to increase the awareness of criticism. If someone makes a seemingly innocuous comment to you, it might pay to stand there quietly and scan the remark for criticism for a few seconds.

The need to detect incoming criticism becomes so strong that the awareness of how odd this behavior is gets neglected and weakens.

tl;dr -- The German Stare is the other guy trying to figure out if what you just said was an insult.