Hm, I had a math professor, that said “good morning” and then started doing some math magic and lost half of us after 2 minutes, and, I am pretty sure, nobody in the class could follow after 5 minutes.
For me, that was the best teacher ever; after each class, I had to put in a lot of effort to try and figure out what had happened. That’s how I learned. He was definitely not the best teacher for everyone.
