Well I went to college after 1970’s but that wasn’t the way it was taught, and my college was in top ten at the time.
However they got here is what it is, and not something I would argue about..just interesting that it sounded like some NEW discovery and I did not equate it as anything new.
The idea was not taught until more recently. Harrison was a student at UCLA in the '60s, and had the idea in his dissertation. There was no evidence to go anywhere with it. Fladmark was writing from British Columbia, and again there was no data to support the idea for a while.
In the '90s the idea began to be supported from a number of places, including the increasingly old dates in both North and South America, and the reduction in the age of the ice free corridor. Pretty soon those two events crossed, and the early coastal migration had to be taken seriously.