I've grown the most as a programmer literally kneeling or standing behind the shoulder of programmers with 5 to 8 years more experience than I had. Those hours I spent in that position was more beneficial than hours sitting in expensive classes, hours spent debugging, hours spent reading, hours spent building new programs... combined.
The speed of great content delivery by watching someone much better than you code can be overwhelming. If the gap in experience is too large, it is like trying to show calculus to a monkey. He's not going to get it, and it will get bored. There needs to be a common ground to transmit common ideas, analogies, and new knowledge. The viewer has to put in a huge effort to keep up.
There needs to be feedback from the viewer to say: "Hey stop, what is this devil magic you are doing right there". And the presenter can stop and explain how this is muscle memory to him.