So there was a sterile space between Clovis and newer cultures. However, how many of these gaps occurred at the same time in widely spaced locations.
What about the Black Mat? What about the directionality of the axes of the eliptical Carolina and other Bays? What caused the Younger Dryas? Why did megafauna and Clovis disappear at the same time?
Yes, if the large animals were gone, it would make sense to use smaller points.