Lifeisshort (and everybody else) -
First, let me echo what has already been said here: You cannot give up. If you've put in that much time studying, then all that's left is to translate that content into results. The reality is the GMAT is only partially a test of content. It is also a test of:
-How well you manage your time in test situations. Most people end up leaving a lot of problems blank, and that hurts more than anything else on the GMAT. If you can't do a problem in 2 minutes and you get behind, stress goes up. Then you can't think straight. So you start rushing. Then you make silly mistakes. You get the picture.
-How well you stay focused on the problem at hand. Most people try to discern how they are doing on the GMAT by thinking about whether the current problem is harder or easier than the last one. This is a disheartening strategy, as it's impossible to figure out how you are doing while you are taking the test. You just have to take it one problem at a time.
-How well you pick your battles. Even if you score a 770 on the GMAT, you are still missing a TON of questions...You just happen to be missing very high level questions. The key takeaway is therefore that you cannot solve all the problems. Sometimes you'll need to guess right away. Sometimes you'll need to spend 30 seconds to narrow down the answer choices. Sometimes you'll need to work for 2 minutes, realize you aren't any closer than you were 2 minutes ago, and just cut your losses.
-How well you can IDENTIFY the kind of problem in front of you. If you are a master of prime numbers but you don't realize that questions about the "Least Common Multiple" are really testing your ability to break down numbers into their prime factors or you are a master of identifying assumptions but don't realize that CR questions that you ask to strengthen or weaken an argument are in large part simply testing your ability to identify assumptions, you're leaving points on the table.
I share all this with you to make one key point: The GMAT is not a test of intelligence and thus your present struggle with breaking 600 is not a reflection of any learning disorder. I would guess that the reason you aren't hitting your goal score is because you aren't studying in the most effective way.
Although this refers specifically to problem solving questions, the fundamental idea is quite simple and applies to all GMAT problems: Don't focus on the fact that you are missing the question. Instead, figure out WHY you are missing the questions. If you don't know the underlying concepts, review those concepts in the books. If you don't know how to solve a problem in 2 minutes even though you know the concept (such as finding a "Target Number" when working with VICs), review that strategy. If a concept is just well beyond your comfort zone and you don't have time to learn it, decide TODAY how to recognize that problem so you can guess on it within the first 15-30 seconds.
Regardless of your area of weakness, you (and others in this post and throughout the forum) need to shift from asking "Why am I only scoring a XXX?" to saying "I am weak in Work problems...does anybody have any suggestions for how to solve them?" or even "Why must a noun modifier touch the noun it is modifying?"
With all that said, here are a couple specific pointers baed on what you said above:
-SC questions: These are all about training yourself to notice splits. For example, if you see a giant part of a question moved around, you should stay aware of either a change in meaning or a modifier issue. If you see some answer choices that have a pronoun and others that have the original noun still there, you want to ask yourself if there are any pronoun ambiguity issues.
Also: When you're getting 9 or 10 wrong in a row and then 9 or 10 right in a row, are those on paper or on the test? If they are on paper, are you working backwards through the books? The
OG questions are organized by difficulty, so you might just be getting to harder questions. Alternately, you might just be the kind of person who needs to warm up. If that's the case, you know you need to do some practice in your car before you head into the test center. Finally, if you're good with SC you are probably good with grammar and thus the way you would choose to craft an answer choice is probably not aligned with the official answer. As a result, you need to learn to look for the BEST answer by crossing off things that are grammatically incorrect.
2. VICs: Train yourself to recognize these problems and then to immediately pick numbers. Honestly. For most people, the algebra is way too time consuming. Picking numbers is an absolutely appropriate and clever way of solving problems, but if you waste a minute with the algebra before you decide to pick numbers, that's a minute you'll never get back.
3. General Quant: If your quant score is so low that you won't even mention it, forget about the score. Figure out where else you have weaknesses and do targeted sets in those specific areas. Think of it like playing a guitar: Nobody learns to play the guitar by running through an entire song, then running it through it again, again, and again. Instead, we learn by practicing the opening riff 100 times, then moving on and practicing the chorus. Then, we play while we're singing. And so on. Focus on solving a problem with a certain concept, and move on to another concept only when you've mastered the current one.
4. Finally: Across all GMAT endeavors: Quality over Quantity. You should not be doing 100s of GMAT problems. You should be spending 8-10 minutes on every problem you do - identify your weakness, focus on finding new strategies, figure out why you got a question right or wrong, and otherwise simply dive in feet first into every problem you do. If you do 20 problems and spend 10 minutes each, that's an entire days worth of GMAT prep.
I know there's a ton here, but let me know if this all is helpful. Shoot me a PM if you'd like to talk more about specifics.
Best of luck,
Brett