Give me a fish and I will not be hungry today, teach me how to fish and I will never be hungry again. Read this article in order to learn how this idea can be implemented on the GMAT test

Those who control many methods will always have to keep learning more and more methods developed by others. Almost every GMAT question can be solved using more than one method.
In order to fully get to know and control a method, as many as 3-4 practice questions are needed. Since there are many hundreds of methods on the GMAT, you need to practice thousands of questions in order to make sure you control every important method needed to solve above 95% of the GMAT questions.
Although there is no way to completely eliminate a comprehensive phase of practice, there is a way to reduce the practice phase so that you will reach your aspired score.

Although the methods used to solve GMAT questions are numerous, the principals used are but a few.
Those who control a principle will easily control the methods derived from it. They will also be able to do something much more powerful: create new methods based on the principle. This explains how some people seem to solve almost every GMAT question very easily - they control the principle it is based on.
This is also why some questions are easy for you while others seem impossible. That’s right, you control the principle needed for your easy questions.

When studying for the GMAT, make sure you use a study material which teaches you both the principles and the methods - not just the methods. Learning the methods alone will take much longer and will not lead to a solid understanding of what the question is based on. When you only know methods, small changes in a familiar question can render it impossible to solve. Knowing the principal will lead to a solid understanding of how to address each question type and what methods will be the most efficient ones to use.