He simply neiled it

Well, Charles Mann blasted the Bering Land Bridge theory out of the water in his 2005 work titled "1491", showing that humans have been in the Americas for far longer than 12,000 years and that the Bering migration is highly improbable and balanced on weak and outdated evidence.
But 10+ years later, we're still learning about the Bering Strait instead of the 3 distinct migrations, as evidenced by 3 distinct genetic signatures and 3 distinct linguistic patterns across development of Native North American languages.

I've only learned about the bering strait, as far as I was concerned that was taught as fact. So... Its not? Or at least not likely?

Not likely at all, and it doesn't explain the presence of human activity in the southern cone shortly after the closure of the pass.
Mann has some other research that is praised and subsequently ignored or discarded. His research on epidemiology and American Natives' lack of immunity to smallpox makes some 90% of the white man's genocide completely accidental (which doesn't excuse the intentional genocide that followed, for the record). That's not popular, so we're still talking about Columbus as a bloodthirsty mass murder a la Adolf Hitler, instead of simply the greedy disease-ridden sailor that he was.

1491, and 1493. Fabulous books about the world before and after Columbus. Packed with science (i.e. entire chapters on topics like the chemical structure of rubber or how potato blight spreads in guano). A great read with unpopular science that goes against some of the "industry standards" in a sense.

@smitty, I’m surprised you challenged guest rather than backing it up. https://daily.jstor.org/why-no-one-believed-einstein/. Scientists disagree all the time. When an accepted theory is challenged the challenger is usually balked at until they can prove or disprove (not always easy). http://www.telegraph.co.uk/culture/books/10654762/The-man-who-proved-Stephen-Hawking-wrong.html

A fair point that has merit, but in the moment the way the wording caught me, it sounded like pseudoscience apologist rhetoric.
The same sort of language dialog that the supporters and defenders of the unscientific use.

"Oh, no one believed Einstein or Newton. The church persecuted Galileo. The church executed Bruno. Their persecutors were wrong. I/they are being singled out and 'persecuted', therefore I/they must be right."

It reeks of a variation of the appeal to antiquity/authority logical fallacy.

Exactly what the quote says, knowledge based on the scientific method is in motion. Of coursed scientists are fallible human beings and - as individuals - may stick to what they have learned. But that's the beauty of the scientific method: in the long term it's going to work out, because it's by definition a collective effort. The idea that scientists "disagree all the time" shows a basic lack of understanding what science is all about. "Challengers" who don't put up sufficient proof are not balked but (rightfully) ignored. I'm pretty sure Stephen Hawking is generally more than happy to be proven (!) wrong when that means gaining more insight and understanding. As to Charles Mann: current state of science may take longer to become part of the school education than to be accepted by peer review.

Which begs the question, "If he's right, and peer review implies such, why should this take any time at all to become part of school education?"

I hate to interject in such a lively and intelligent conversation, but does anyone need any muffins? I have blueberry, macadamia nut, chocolate chip, and double fudge.