Our neocortex is certainly the main reason that we are "special". What is interesting though is the number of "pre-adaptation" that needed to be in place before such a development could take place. However, as I hypothesized in the article, I don't believe that once an animal possesses some type of cultural ratcheting that it starts to progress very quickly. Since ratcheting seems to be an exponential phenomenon, I believe the process likely starts off with an unnoticeable beginning. If you were to study the first australopithecines, you would likely not notice any type of cultural ratcheting, even if you observed them for thousands of years. In fact, you would hardly notice any cultural ratcheting in Homo erectus. They used the exact same tool technology for 1 million years! However, in retrospect we can observe the archaeological record and see that in fact the technology was improving in complexity exponentially, and it had yet to really hit an explosive curve.