Some context: Tim growers follows the pedagogical style of producing the proofs on the blackboard in front of you without notes. This is reasonably possible in

Some context: Tim growers follows the pedagogical style of producing the proofs on the blackboard in front of you without notes. This is reasonably possible in the kind of pure mathematics where his interests lie. The idea is that it forces the kind of straightforward proofs which have few ideas and are mostly doing only the obvious thing. It also means the audience get to see someone actually doing it rather than just presenting some notes. Morally, I want to say this style is good, but I don’t really have any idea if it’s the best way to lecture something. I saw an attempt at something similar to this video—trying to solve a mostly unseen problem in real-time—from him about 5 years ago. In that case it was some attempt at an IMO problem and I think he got stuck at the end which relied on some weird equivalence classes of functions which were apparently quite common in IMO questions at the time but hard to derive if you’d not seen them before. He has a reasonably popular blog at growers.wordpress.com where he has run some “polymath projects” which were attempts to prove or disprove certain conjectures through wide scale collaborative mathematics over the internet.