Even though to just say the words of what you are studying does not take the place of in depth learning "Iyun", I still think it is important. You can see this in the LeM of Rav Nahman vol I section 74 where he specifically goes into the importance of in depth learning/iyun. This clearly is not meant to disagree with Conversations of Rav Nahman  76 [Sichot HaRan section 76].

And though Rav Nahman meant this for learning of Gemara, it also applies to Math and Physics.

[I have mentioned before that these are called "secular" by mistake. They are not secular, but rather the wisdom of God embedded in the Work of Creation.] you can see this most of all in Mishna Torah of the Rambam laws of Talmud Torah chapter 3 where he brings the law to divide one's learning into three parts: (1) Tenach [Old Testament.] (2) Oral Law (Mishna). (3) Gemara and the Rambam  adds there  "in the category of Gemara are the subjects brought in the first four chapters of Mishna Torah". [Physics and Metaphysics.]

Those four chapters are Aristotelean Physics and Metaphysics