There is a major point that I gained from the advice of Rav Nahman that I wanted to share. One is the path of learning. Even though the idea of learning fast is common place in the great Litvak yeshivas based on the Gra, still Rav Nahman puts it in a way that makes it possible for even small mediocre people like me to get to  levels of learning. Say the words and go on even without understanding. The deeper reasons he said this might be many. However I found this to be a great benefit, whether in Torah, or also later in Physics.  For if I had gotten stuck on  every single point in learning before I could go on, I never would have gotten anywhere. However, the only way to get to authentic Torah learning is through the Gra and the great Litvak yeshivas. But if one is in a authentic Litvak yeshiva then the advice of Rav Nahman is an amazing help.

[And in Litvak yeshivas there is an emphasis on review and learning in depth. What seems the best to have some kind of combination. For example, half learning in depth and the other half just saying the words and going on.]