Most people think of the GMAT only as a rigorous test of logic and higher reasoning. It tests your ability to think on your toes, and react quickly to a barrage of information. Most people assume that the more they think like a supercomputer, the more successful they will be. But I think that even though reason has its place, the GMAT is also amenable to creativity. Specifically, I have seen a number of questions in quantitative especially that employ lateral thinking for quick solution. Questions test your ability to apply concepts, not hammer through laborious calculations, and as such, they demand whole brain thinking.
Still, routinized logic has its place in the GMAT. Take for instance the rules of grammar, which are not flexible. Or take for example the watertight logic of critical reasoning. However, flexible thinking can be effective even in these scenarios. One may for example use a creative approach to eliminating wrong answer choices in sentence correction. They might be better able to think outside the box and conjure up a circumstance or scenario that spoils or saves an argument.
My point is don't discount creativity and lateral thinking on the test. We are human, we are not computers. In spite of our search for perfection, and the perfect GMAT score, or at least our personal best, we are liable to err. But we can use our special, and wonderful minds to see through this test, get into the minds of the test makers, and come up with creative ways of solving problems and chopping down time. These are things a computer can not do.