When I read something (mentally), I can see that there are two parallel processes that take place:
1. The "physical" aspect of mental reading - mentally sounding out the words that are in front of me. This is quite fast already and is pretty mechanical.
2. Converting the words into meaning and registering it in my mind. This is the much harder task, and you actively need to focus to do this.
To see that these two are indeed parallel processes, notice that it's possible to "read" something in your mind without any of it actually registering while you think of something else, say a narrative about just how awesome your life would be if X or Y were true. I often have to actively break the internal narrative and pull myself back to focusing on what's read.
The focusing part is the real bottleneck, not the mechanical reading part. This is painfully obvious especially when you are trying to learn information-dense material such as Mathematics, where you have to pause to recall definitions, follow argumentation, and so on.
1. The "physical" aspect of mental reading - mentally sounding out the words that are in front of me. This is quite fast already and is pretty mechanical.
2. Converting the words into meaning and registering it in my mind. This is the much harder task, and you actively need to focus to do this.
To see that these two are indeed parallel processes, notice that it's possible to "read" something in your mind without any of it actually registering while you think of something else, say a narrative about just how awesome your life would be if X or Y were true. I often have to actively break the internal narrative and pull myself back to focusing on what's read.
The focusing part is the real bottleneck, not the mechanical reading part. This is painfully obvious especially when you are trying to learn information-dense material such as Mathematics, where you have to pause to recall definitions, follow argumentation, and so on.