It is at this point that Tony and I really diverge. I see no evidence in Siberia, especially in the Beringian area when there is a Middle Paleolitic-like flake technology that could be Tony's first Americans. To my knowledge, all of the assemblages include a dominance of microblade technology, even if there are other technologies. I also don't see the evidence for the dates back into and before the last glacial maximum at around 20,000 years ago.
Although I see what Tony is getting at when he says that if there was an early flake-dominated technology, it wouldn't be recognized by many amateurs or collectors, I don't think this really explains why some of them (like Tony) haven't recognized assemblages like this if they were here.
Professional archaeologists have also been on the trail of pre-Clovis for at least 25 years now, and with only a couple of possible exceptions (Cactus Hill in Virginia and Meadowcroft in Pennsylvania, both dated to between 15 and 17,000 years old, and Monte Verde in Chile, dated to 12,500 years ago), we can point to no Middle Paleolithic-like assemblages from pre-Clovis deposits.
I have also been privilaged to work in Middle Paleolithic sites in Europe and SW Asia, as well as studied materials from Africa and Asia, and if I had seen these things here in the New World, I surely would recognize them (as would many others).
Either use the back button on your browser or go back to Tony.