As a lithic technologist, I've always said that the ultra-difficult fluting process had to be preceded by something simpler and easier.
However, these authors are sandbagging the data by showing only coastal sites -- and by ignoring mid-continent pre-Clovis sites like Gault in central Texas.
~~~~~~
FWIW, I'm on an archaeological listserver where posting this article would start a weeks-long fight. Believe me, the "There warn't no people here pre-Clovis!" cadre is still alive, kicking and vociferous in professional American archaeology. Even the mention of Dillehay's name suffices to set them off...'-)
Thanks for the link; maybe I'll go "rouse some 'stuffed-shirt rabble'" among my colleagues with it... LOL!!