This is incredible! Is the code open source?
Not yet, but it will be soon!
It doesn’t look like it but there is a draft of the paper available: https://arxiv.org/pdf/1707.07397.pdf
They have a «code» link that says «coming soon» — so, not yet, but hopefully it will be in the future.
I think it really depends on the subject you’re learning. If you’re learning some sort of theoretical domain, such as analysis, you certainly have to work through every theorem - otherwise you won’t really understand the course of the subject. On the other hand if you’re learning applied calculus or linear algebra working through every theorem probably isn’t as great - by the nature of the class you’re already skipping over tons of theoretical details. I don’t like the black and white tone of this article.