I would say that the dip in score is because of faulty preparation and faulty prediction (if you ve skipped AWA during those practice tests).
Taking more and more practice tests or working out more and more problems will NOT improve your content knowledge or test taking skills. Infact you will only get better at using WRONG strategies for the exam.
Below is a small section from my blog on how to prepare for SC. Follow the same rules for CR (practice topic wise and learn from each question, redo and review all questions including the question you got right in first attempt) For RC, follow Gin's approach. just google and you will find it.
Also i suggest you to build strategies for each section in GMAT. NEVER Underestimate the GMAT. Its an adaptive test.
Methodology:
For Friends who have just started with SC preparation:
If you are in the initial stages of SC preparation, then learning and practicing topic-wise is the best way to start, just as mastering the individual nuances of swimming or any other game.
Step 1: Read a Chapter in Manhattan SC guide. Follow the same sequence as in the table of contents.
Step 2: Attempt the OG questions given at the end of each chapter. While attempting the question, try to find out the correct answer option by using the concepts you learnt in that chapter. Try to avoid using your knowledge from previous chapters. What I'm asking you to do is "TO HIT THE BULL's EYE". Don't worry if you get a few wrong. Don't read detailed solution given in OG right now. There is a reason behind this advice. If you have Verbal review book attempt those questions too.
Step 3: Follow the above two steps till chapter 10. Then follow the steps mentioned below for test takers who have already been preparing for GMAT for a month or so.
For Friends who have fair idea about the SC concepts
Step 1: Read a Chapter in Manhattan SC guide. Follow the same sequence as in the table of contents.
Step 2: [MOST IMPORTANT] For each practice question at the end of a chapter write detailed solution on a sheet of paper. Write down why the correct answer option is correct and why the incorrect answer options are incorrect. While eliminating incorrect answer options you can use your knowledge from other chapters.
Step 3: Once you are done with the OG questions compare your solution with OG solution. This is because each question in SC tests more than one concept. An incorrect option might be wrong due to more than one reason. By comparing with OG solution, you will come to on what basis OG eliminated that option.
Step 4: follow the above steps for each chapter. As you progress from one chapter to another, try to apply the concepts you had learnt in the previous chapters.
Note: Some of you might be lazy to write down the detailed solution. I strongly recommend you to write on a paper rather than mentally eliminating the answer options. The detailed solution would come in handy when comparing your solution with OG solution.
What are the benefits of this methodology?
1. Best utilization of each OG problem
2. By following the above methodology you are using THE MOST important strategy in verbal section: POE - Process of Elimination.
3. By reviewing all the 5 answer options you get a better understanding of concepts. You are also improving your application process.
Only drawback!!
Writing detailed solution for each OG problem is a time consuming process.
40 Minutes spent solving 10 questions using the above methodology is certainly better than solving 20-25 questions in 40 min. The most important thing in a study session is what you take-away from each study session.
