For me the course has already been greatly beneficial and I'm finding excruciating that the obligations of a 'day job' don't let me engage and commit fully to this opportunity to squeeze out all the goodness. In my case I cannot afford to fight the puzzles but in weekends I sit down and advance the book and the lectures religiously and do choosen problems. Ch. 3 is a difficult passage and I invested a couple of weekends convincing myself I was confortable with it, writing down in full a left Kan extension. After that I got tired and had to delay ch. 4 to summer holydays that I started enjoying, so I'm going to get ahead of schedule again. I reaped sweet benefits from the course. The concept of Kan extension is written in the books, but It wasn't until being told here from mouth to ear what it was, that I understood it. The political analogies of liberal and convervative adjoints are perfect also and pure oral tradition, not in textbooks. Now we are visiting enrichment that is exactly what I need to access certain writings of Willerton. I was amazed by the energy displayed and would understand whatever has to happen, for all the effort already freely given, thanks.