I tried doing your method for reading on one of my practice tests, and it took me a whole minute to look over the questions and make all the line markers. After ten minutes I was still only 6 questions through on the first passage so I raged and gave up. A strategy that worked really well for me and got me my highest ever reading score (32) was the “four corners” technique. You read the first one or two paragraphs in its entirety (one or two depending on the size of the first paragraph), and then you just read the topic sentence (first sentence) of each paragraph until you get to the last paragraph in the column (or the corner paragraph). You then read the entire last paragraph of the first paragraph and the first paragraph of the second column (It might just be the same paragraph in each column). You then read just the topic sentence for any paragraph in between the corner of the second and third columns (if there is a third column). Once you get to the last paragraph, read it in its entirety. Sorry if that’s confusing. If it is just tell me and I’ll try to give a visual representation. I’m a really slow reader, and it usually takes me over 4 minutes to read the passage, and this cut my time in half. I really didn’t lose any of the information either, however it doesn’t work very well with prose fiction since it’s setup like a story instead of an essay, and you have to pay a lot more attention to specific details in prose fiction. For that reason, I did my passages in the same order as you. I used the four corners technique for Social Science, then I used it for Humanities, then I used it for Natiral Science, and then lastly I read Prose Fiction normally.
For Science I tried to go straight to the questions for the April test and it went horribly. My best ever for science had been a 25 (I’ve always had trouble with it), but my science score when I went straight to the questions was a 22. For this test, I gave myself 2 minutes to read the passage and look at the graphs, and then I gave myself 30 seconds for each question. Trust me, it’s extremely beneficial to at least have somewhat of an idea of what’s going on in the experiment. When you look at a question, cover the answers and try to find the answer on your own. Once you find the answer, pull your hand off and make sure that your answer is an option. Don’t cover the answer for the “which of the following” or the “except” questions, for obvious reasons. By the way, I got a 31 in science this test, which is my best by 6 points.
Really the key is to take lots and lots of practice tests. Test day can’t be the very first time you try a technique. Definitely practice with the four corners technique. Good luck!