Dear iamnanmu,
The frustration you feel is valid on a lot of levels. At the same time, I feel like you are trying to eat an entire Elephant in a single bite.
Like any manner you study, studying happens on what? Layers and repetition. This is universal. Even in photoreading, I study the same thing over and over.
If you study, your course with no interest. Expecting Photoreading to charter you through entire course (That's what I was expecting). One is bound to fail.
Take a moment, change the approach towards your course. Have no expectations. Forget about your deadline to study it. Just get engrossed in this subject for a while.
Use prepare, photo-focus, and p/review stages, as a substitute to your normal reading. Here you have set yourself in motion to learn.
Then use the activation sessions, for comprehension. This is where you can use many techniques. Don't get stuck to a single method. If reading helps, do it. Drawing helps, draw it. Does writing do the trick, write it all down. Be as playful as possible.
I would emphasise going in the activation stage with a purpose. If you aren't able to find a purpose at first, I used to do something like this. I used to make an arbitary purpose, just related to the topic. This would be as simple as possible. Once I found it, I would end my session there. Then after a 5 minute break, come back and set another purpose. The sessions sometimes just took a 1 minute, some even 5 minutes. Eventually, I increased my session to 20 minutes, with much better purpose.
For example, say I am reading 'Basic Economics'. I would set a purpose, 'What does commodity mean?' It is something I knew before reading. The adventure lies in finding it in the book. Once I found it, I then take a break. Pretty much just before resuming the session, I come up with some purpose. If I am not able to, I repeat the process.
You may not like this method, thus experiment in this session. And always use different techniques.
Some things, that we study, there is no option but just to mug it up. It is not a sign of failure of the system. It is a sign of practicality.
I have experience with finance. Where I was able to understand the formula, just by a glimpse. I could disintregrate it, look at individual components and build-it own my own, when I needed. First it all started with mugging it up. Along the sessions, I grew the logic and the idea behind it. Now, I can tweak these formulas, understand the assumption it was based on. Also pin-point it back to history, as why that thinking was the norm.
Hope this helps.