Very much agree with you. My own experience with calculus specifically is that I would attempt a problem or example myself, then review the solutions and if I'm stuck, I would not understand a proof or solution unless I copy out every single line as the lecture/textbook and even add to it.
The act of slowing down to ensure every line makes sense to me is one of the most valuable things for my learning.
The act of slowing down to ensure every line makes sense to me is one of the most valuable things for my learning.