In many ways, I agree. I have an engineer's understanding of math for my discipline but topology is most definitely not one of them. Through his graphics, I could most follow the gist of what he was attempting to get across but when it was over, I honestly had to ask my self, what did I just watch. Perhaps watching it again, really concentrating on it, and trying to understand, might help, but, in reality, it is so far out of my interest zone, I'll never do it.