> you almost never actually interact with people more than a half standard deviation away

I wasn't talking about the average person there but rather those who could also craft the high undergrad to low grad level explanations I referred to.

> This has not been a remotely credible claim for at least the past six months

Well it's happened to me within the past six months (actually within the past month) so I don't know what you want from me. I wasn't claiming that they never exhibit evidence of a mental model (can't prove a negative anyhow). There are cases where they have rendered a detailed explanation to me yet there were issues with it that you simply could not make if you had a working mental model of the subject that matched the level of the explanation provided (IMO obviously). Imagine a toddler spewing a quantum mechanics textbook at you but then uttering something completely absurd that reveals an inherent lack of understanding; not a minor slip up but a fundamental lack of comprehension. Like I said it's really weird and I'm not sure what to make of it nor how to properly articulate the details.

I'm aware it's not a rigorous claim. I have no idea how you'd go about characterizing the phenomenon.