Actually Go Blue - and I can only hope that means Michigan (wolverines!) - you are on to something. I have worked with students who had timing problems and helped them to work a strategy similar to what you are describing and two students in particular were able to see very significant score increases in just the 24 hours before their tests using the ideas below (very similar to what you are talking about).
The GMAT is a test of time management and if you know that a question is likely to take you more than 3 minutes you are better off getting away from it. Your strategy does make sense, but let's refine it some, because as karanrulz4ever indicates it would be difficult to know within the first 10 seconds how difficult a question is...however, if you do wait until 2 minutes then you do not get any of the needed time to add to other questions! So we need to go somewhere in between, give yourself enough time to see that the question really will be difficult FOR YOU, which is the only difficulty that truly matters when you are in the thick of the fight. So for quantitative please take a look at the strategy outlined below (this is a partial quote from an earlier post of mine):
"The better way to approach the quant section is this:
When you see a question that you can get right - devote the attention and the time that it takes to get it right. There is a difference between struggling for 3 minutes to come up with a strategy for a question you find very difficult (this is usually a mistake) and spending three minutes doing what it takes to ensure that you get a particular question (that you know you can solve) correct. It is a matter of approach to the test and it can make a huge difference. Do not try to steal 20 seconds from questions that you can get right only to hand that time over to a question that you will likely miss anyway.
Here are two things to think about:
1) If you do not have a specific strategy for solving a quant problem in about 1 minute and 15 seconds then you will want to choose from the viable answer choices and move on. It is precisely this type of question - where you have no strategy for a long time - that can sap the time and energy right out of your quant section on the test.
2) Set a time standard for yourself - I like to say that after question 25 I should have 25 minutes left (for the last 12 questions). If I am 5 minutes behind, I will just skip (randomly guess) at the next two problem solving questions I see. This will bring me back to the right pace. This is a better strategy than the alternative of " I can catch back up." Be careful here, trying to catch up usually means saving 20 or 30 seconds per question and we already know this is a mistake. Better to sacrifice two or three questions for the good of the test.
Finally, focus on getting questions right rather than on fearing that you might get some wrong. You will get questions wrong. But if you get say, 30 of the 37 right you will be in great shape.
And just a note as to the idea of educated guessing - I am not big on educated guessing on the Quant section if it will cost more than a few seconds. The GMAT is really set up so that there are only two outcomes - you did everything you could on a problem to avoid errors and you carefully worked thought so you are as close to 100% sure of the problem as one can get --- or you guess. It really does not matter that much if you guess from 5 choices or guess from just 2.
Here is why:
If you do guess out of five you have a 20% chance of guessing correctly and given the significant number of non-counting experimental questions you have about a 20% chance that any question you face will be experimental. So if we subtract the overlap that is around a 35% chance that a question you guess on without even reading it will not count against you.
Now let's say you take 2:30 minutes and get down to two choices - that must be a much better situation right? Not really. There is still a 20% the question does not count and a 50 - 50 chance of getting it right. Subtract the overlap and you have a 40 to 45% chance that you guess right and it counts. It is true that you have more than a 50% chance that the question will not count against you but it is not worthwhile for your 2:30 minutes investment to get a 45% chance of getting credit for the answer.
What if you work a problem all the way through and take care to get it right? Now all you have to worry about is that it is experimental. So here is an 80% chance of it counting for you and only a small chance that you made some silly mistake and it counts against you.
So you see, if you can do a problem then take the time to see it through up to 3 minutes is a good investment. If you cannot see a way to confidently work the problem it is better to guess early rather than late.
For Verbal you should be able to find a way to make it through...how are you are sentence correction? That is really the key to finishing the verbal on time. Let me know if you need some ideas to move through sentence correction more quickly.
