Watched this today---kind of repetitious re-hash of the Cretaceous event, then nice shots of various guys digging in a black layer, research on hexagonal diamonds which was fund to see because it was at my old alma, UCSB.

Upshot it...nobody knows for sure what happened in 12900 BC...except that most large mammals and the Clovis culture disappeared pretty suddenly.

I was rather disappointed in the show.