You know you know the material when you can understand everything at the speed it's presented. (Chopping everything in 2-5 minute blocks helps with that too. Worst case, memorize everything and move on.)

[also, the posted content was part of a second level linear algebra course, so a lot of it is presented as a series of bullet points with just enough detail to jog existing memories of terms/definitions/how things interact.]

Also, that's just some kind guy who has a PhD in particle physics at Princeton who volunteered to let me record him saying things with no coaching or guide at all. There was zero coordination between the hour he talked while I recorded him versus the month I spent adding incoherent flying equations everywhere.

You know how Michael Bay movies are horrible because he wants to throw in every CGI effect he can? It was like that. I wanted to experiment, pedagogically, with different kinetic visuals. I feel my knowledge spatially/visually, and video is a perfect medium for toying with spreading "how I think."

You should have seen the first version I had with tons of explosions and racially stereotyped eigenvectors.