highdiving
So it's actually about how soon you can reach (say) 700+ level questions and how many of them can you answer correctly, instead of the test trying to zero in on your level?
I don't quite understand what you are trying to say. But don't waste time gauging the question difficulty, its a complete waste of time. A 600 level scorer will take more time to reach that 700 solve because of difficulty and careless mistakes, while 700 level test taker will be able to move quickly to that level and also stay on that level for a long time. All the GMAT questions can be solved, but what you do in stipulated time determines your score. If you spend more time to increase your actual capability, then once you reach that level it takes half the time to reach the level where you started because you cannot keep on spending more time for every problem and for every additional minute or seconds you spent initially to improve your level, you have much less time for each of the latter problems. So the key is to get good at content knowledge, know your strengths and weakness, guess where you need to and where don't need to and reduce careless mistakes.