Both learning in depth with lots of review and learning by just saying the words and going on are mentioned in the gemara.''לעולם ליגרס אינש אע''ג דמשכח ואע''ג לא ידע מאי קאמר'' ''Always one should learn fast  by just saying the words even though he forgets and even though he does not even know what he is saying.'' And there is the event where one teacher was teaching each his lesson to his student 400 times until he understood. Then one day the student was not paying attention, so the teacher taught the same lesson another 400 times. Then in that merit, he was granted 400 years of life and that all the people of his generation would merit to the world to come.

So you need both. my suggestion is to do the in-depth learning in math, physics and gemara [talmud] in the morning and the fast type in the afternoon and evening as is the regular order in most Litvak yeshivot. [However, I do not think that Shar Yashuv had any set time for fast learning,-- as all the learning there was in depth.]   [My son, Isaac, told me many times that the main thing is in depth learning, and that fast learning (saying the words in order and going on) should only be after one has completed his in-depth learning sessions.]