Here's the thing about prethinking on CR questions:
1. The GMAT is a time pressured test
2. Your job isn't to come up with the perfect answer, only to pick between 5 answer choices
3. Unless you're aiming for a sub 650 (classic GMAT) score, there's no point pursuing a strategy that works better for easier CR questions and not so well on harder ones.
Put all those things together and excessive prethinking doesn't make sense.
It's important to understand how the GMAT makes hard questions hard. Remember they're looking for executive reasoning skills. They test it by using psychometrics to make you miss information and or in the case of CR, over including information from the prompt when all you should be focused on is the core argument.
There are two key prethinking things that help in harder CR questions:
1. Reading the question first so you know what angle to read the prompt from (it's totally different if you're looking for weaknesses or assumptions compared to inference questions)
2. Distilling the core argument / point / conclusion down to 10-15 words. One of the biggest problems is carrying too much of prompt along with you when they ask you to analyze the strength or weakness of the core argument.
Anything more than that is a waste of precious test time - the answer choices limit the range of thinking you should do beyond those two things. Spending anytime wandering around the prompt and thinking freely outside the range of the answer choices doesn't work.
Remember also that the GMAT rewards you for great CONSISTENT process --- just like sports. Great hitters, shooters, passers follow a consistent process for each swing or shot they take. They don't score every time in hard (ie. 700+ situations) but you don't have to to be among the elite. It's the same with tough CR questions. You just need a consistent and EFFICIENT CR process that puts you in the game on hard ones and lets you get a majority of them right.
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Arvind
Lead GMAT Performance Coach
RetaketheGMAT / i4Excellence Elearning
Tel / WhatApp +1 305 814 9299