I totally agree with you and that is why I have also added to the post the link to the open course MIT site. I also believe that is quite naive thinking that y

I totally agree with you and that is why I have also added to the post the link to the open course MIT site. I also believe that is quite naive thinking that you can learn math in some depth just watching videos (at least with my capacity). For me it is a way to keep some pace and order when learning and, as you say, to find some bibliography and material that is being used by the professor.