One thing that I think many young conductors do not realize is how you really do need to know every note of the music. At one point in the video, Lenny states that there are 55 notes in the first measure alone and if the conductor doesn't know every single one of them, he has no right to be standing on the podium in the first place. I also liked the part where he talked about conducting with your left hand behind your back. It seems very common to watch yng conductors do all kinds of excessive movements that clutter their clarity or just don't serve a real purpose. It drives me crazy to be conducted by bad conductors!