790 (Q51, V51) Debrief with Various Tips

I took the GMAT today and scored 790 (Q51, V51). Since I read some stuff on this forum from time to time, I wanted to give tips I found useful. I will focus on answering the questions I was trying to answer when starting to prepare for GMAT three months ago. If there are any other things that you'd like to know, let me know.

OK, on with the de-brief...

Resources I used to prepare
-Official Guide for GMAT Review 2016 (called here OG16 I suppose)
-Official GMAT Verbal Review (mainly because I mismanaged time and had too much time during Christmas and wanted to practice to keep in shape)
-GMATPrep software from MBA.com, including the Exam Pack 1 for $50 (cost me 33 GBP with taxes)
-Manhattan GMAT guides: Sentence Correction, Number Properties and Word Problems. Out of those three only the Sentence Correction guide I'd recommend buying without even thinking about it if you need to improve in SC.
-MGMAT CATs (included with each MGMAT guide)
-Manhattan GMAT test simulation booklet (so as not to get shocked by the laminated things you need to use in the exam)

How I prepared
1. Took GMATPrep practice test 1 to see where I stand and where I need to improve the most. As written elsewhere, in my experience nothing predicts your GMAT score as well as performance on the GMATPrep tests. Some people write it's a waste of a test to do one straight before you have dony any studying, but I don't agree. It's very useful in giving you as accurate prediction as possible about where you should focus your efforts. Not doing GMATPrep at the start to me is the same as trying to restructure a company when you don't know what the current problems are. You can buy 2 extra GMATPrep tests for like $50, so you have 4 tests altogether ($50 is good spend if it can save you week or more of effort).
2. Based on GMATPrep Test 1 + some questions on OG16 + MGMAT CAT 1, I determined I need to study up on Sentence Correction (I am not a native English speaker), and then refresh Quant a bit.
3. I read the whole Manhattan GMAT SC guide, which did help me quite a lot. I am not the best in remembering arbitrary rules, but through reading the guide and then doing the CATs I managed to remember the most important ones.
4. I skipped doing any prep for CR and RC and just did the hardest 1/3 of the questions in OG16 to confirm I was right in that assessment, and I was - I got success rates of 80-90%, so didn't really do anything more there.
5. For quant I quickly flipped through MGMAT Number Properties & World Problems, but after that just did OG questions + CATs to learn all the gotchas (of which there were quite a few).
6. After all that I just did the MGMAT CATs + at the end GMATPrep CATs to confirm.

On the topic of Manahattan GMAT CATs
In my experience MGMAT CATs underestimated my score consistently by ~40 points and the questions, if you are doing relatively well, are harder than on GMATPrep. On top of that, a small percentage of the questions in Verbal (maybe 10%) is plain wrong, in that none of the answers (including the one given as the correct answer) really make sense. I am saying this not to critize the tests (they are in fact really good in terms of preparing you for the real thing), but merely as points to bear in mind when you are analyzing your test performance. For example I was unhappy that I'd always get 4-5 CR + RC questions wrong, but analyzed the questions in depth and concluded I don't need to do any extra prep for CR and RC because the questions had problems. That saved me from wasting time (on GMATPrep 2,3 and 4 I got 0,1 and 0 verbal questions wrong respectively).

The thing MGMAT CATs are really good at, maybe even better than GMATPrep, is in teaching you how to manage time - because even if you are really good you don't stand a chance of answering every single question, you have to learn to let go of a question after you run out of the 2/2:30/3 mins that you can spend on it, and you have to learn to manage your cumulative time well. More on time management below.


Strategy - Time Management
THE topmost important part of strategy in my experience is time management. Honestly you can be as good as you want in both quant and verbal, but if you waste 6 mins on a single question that you in the end fail to answer correctly, and then another 6 mins, and then you have 1 min/question left for the last 12 questions, nothing will save your performance. That's how it felt to me. So I have sort of 2 rules that I came up with:

Rule #1: Never get more than 3 minutes behind the target time (e.g. on quant if I've done 10 questions so far, I should have at least 75-10*2-3 = 62 minutes left). Getting too far behind as described above is basically impossible to recover from (in my view).

Rule #2 (helps to execute so that rule #1 is observed): If you are beyond 2:30 of time spent on a question, and don't have extra time to spare, then guess and let go. I had to do this on MGMAT CATs from time to time, very rarely on GMATPrep or real GMAT (although happened once or twice on real GMAT). One thing I'd say is to apply obvious judgment to this. If you have 10 questions on Verbal and 30 minutes to go because you've been fast on the previous questions, then 3 minutes per question is fine - maybe even 3:30. So long it's not getting you into a time deficit.

Tip: MGMAT CATs allow you to export your timing information question by question to Excel. This allows you to make a detailed timing analysis, such as chart your time deficit (optimal cumulative time taken - actual cumulative time taken) as you go through the test, which I found very useful in debugging my timing problem. An example of the sheet is attached to the post.

Caffeine Corner
Maybe less useful, but for me as important as other stuff: On the exam day (and on the mock CAT days) I always get myself caffeine-loaded. By that I mean I have one 350ml (the bigger can for people in the US) Red Bull and a coffee/coke. I did this for GMAT and before this for all the 3-hour continuous exams I took at Cambridge and I think it's always done well for me, because while it doesn't generate extra knowledge in my head, it for sure makes me faster and also makes me notice and not forget many important details. That being said, for these things to have maximum effect I normally drink coffee only twice a week (so I don't get tolerant) - not really sure how much I'd pick up tolerance if I drunk coffee once every day, but for important exams I want to avoid doubt.