You are correct that on the GMAT - as opposed to most other tests - the writers of the test do seem to be trying to "fool" you!
One of the big things is recognition of the problem. Here are a few things that might help:
1) It is nearly St. Patrick's Day again so enjoy this article from Brian Galvin about Shamrock Milk Shakes from McDonald's and the way that the questions are the GMAT are cleverly disguised versions of questions that you have already practiced.
https://www.beatthegmat.com/mba/2011/03/ ... t-the-gmat
2) One of the things that you could benefit from is knowing how to "diagnose" the question before you do the actual math part (which it sounds like you are pretty good at). Here is an article called Diagnose your way to success on the GMAT. It gives you some drills to help you..
https://www.beatthegmat.com/mba/2012/04/ ... at-success
3) It can help for you to gather together all of you information before you just jump in to a problem. Here is something that discusses this concept.
https://www.beatthegmat.com/mba/2011/06/ ... nt-section
4) You need to develop strong habits and procedures for each type of question - that way you can recognize what is different. If you have a good strong procedure that you follow - for example on data sufficiency - then you will recognize the underlying concept being tested (and you will not make those silly errors which are such a big part of the GMAT).
https://www.beatthegmat.com/mba/2012/10/ ... -handrails
5) Finally, you do not want to allow the GMAT to use your own momentum against you. That is why you have to stay skeptical and balanced. Things are not always as they appear. Don't let the GMAT catch you leaning and throw you to the mat. This article on wrestling and the GMAT can help you to keep from getting pinned.
https://www.beatthegmat.com/mba/2012/07/ ... ould-it-be
These article should help you to start to get a feel for what the GMAT is doing and how to counter their moves!
David
