I think lectures are better/detailed due to feedback from the audience. The lecturer can guess when to go fast and when to go slow(and explain more) by gauging

I think lectures are better/detailed due to feedback from the audience. The lecturer can guess when to go fast and when to go slow(and explain more) by gauging the audience. In some cases the author of a book can guess what his audience can think and provide explanations in advance. But thinking what your reader might think is hard. I feel in the case of the author of the article it was just an accident that he is very similar to the audience that was present during the video lecture.