To learn from the middle and outwards

One thing I heard in high school by an assistant to the physics teacher. To learn from the middle and outwards. [He also said from beginning to end and from end to beginning.] This idea is a great help in learning Physics since it is often the case that I need review to understand what I am learning. But review in itself can be hard to know from where to start. So, what I do is just to start where I am already holding in the book--for example Polchinski's String Theory Notes. [The idea is to  just start from where i am already holding [e.g., page 60] and then to go back to the previous section and from there just to say the words in order until i get to where i was at page 60. and then to go back to two sections before and from there also to work forward to page 60. etc until I get to the beginning. The idea behind this--that makes it worthwhile- is the books of Musar which go by Rav Saadia Gaon that Physics and Metaphysics are in the category of learning Torah. [However, this is an argument among the rishonim.] However, after trying this for a while, I went back to this approach: Just say the words in order out load and then go on. Do review only after you have finished the whole book. And do review four times--