I got a 24 RC.... SO here are my thoughts.
Search and Destroy is relative: to some, it means don't read the passage, but rather answer the question being asked. Once you answer, time to search again.
I used search and destroy, but I would not prescribe the previously described method WHATSOEVER!! You need to actually read the passage.
What I would do was this: read the question being asked. Remember, you can only have one question at a time. When you take the test, you have the passage and you have one question at a time. Keep the question in the back of your mind and completely read through the passage until you find the answer. Your questions on the RC section will usually be in consecutive order, meaning that Question 1 will be in paragraph 1 or 2, and question 2 will most likely be something pertaining to the passage after what you have already read. Once you answer the question, you will click next and it will reload the passage and a new question. It is good to be familiar with the passage and the different sections of it in order to navigate where you need to be reading in your mind.
I think this was important for me, making me able to score better than most everyone else. That, and my passages were ridiculously STUPID hard. I had so many big, long chemicals, I feel sorry for the run-of-the-mill biology majors taking the test. I'm a biochemistry major, having done tons of lab work, scientific literature reading, and soon - research, I was able to wade through the sea of parentheses, dashes, R and L's, etc. I've also read non-fiction on physics and mathematics since early high school(I wanted to be a physicist in high school).
After I realized that Physicists didn't get paid to sit around and try and understand the nature of the cosmos, probing the very fabric of existence, I knew I would rather study the sciences in college and find a job working with people rather than grading papers. Clinical work seemed perfect for me, and now, a few years later, I'm 100% sure I don't want to do anything other than work on teeth!
Good luck studying for RC. If you read through what I said multiple times, making sure you get what I am saying(or at least think you do), I feel like you will have a shot at a good score.
Don't be worried about being a slow reader, I am a slow reader as well. I got a 20 on the reading section of the ACT, but a 31 in science, not having studied for it ever. Scientific understanding is my strong-suite, and comprehending language and communicating is probably one of my best skills. I am an extremely slow reader, even on my RC portion of the DAT. I'm only slow because I take time to visualize, explore all possible nuances with given situations, and truly comprehend what I am reading. Read articles at both Science and Nature websites everyday. That should help. Theres lots of other good reading suggestions on SDN.
EDIT: I realize I went on a LONG tangent; this was intentional practice for the OP! Hahaha