As for the shorter study window, it's really more about retention. If you drag out studying for 4 or 5 months it really means you have to remember what you studied on day one longer. I do believe a shorter time frame with more intense study windows is best, i think if your goal was long term retention was your goal expanding the study window would be best, but in this case the data is a one time use (the exam). I am not aware of any official stats on the subject.
As for the sims, I guess it's something about partial credit. Also, I dont think you have to rely 100% just on what you study. Drawing a few T accounts out can lead you to an answer and in the Sums I feel like you habe the time to do that unlike kn the MCQ. I think the research question is a gimmie. You can search the authorative literature like google. Practice keyword searches and that one is a guaranteed pass. DRS problems I think are a blessing as well. People kind of freak out about them but I find these seem to be problems less about tripping you up which means it should be easier to deduce the answer. I wonder if people get so wound up about the exam they expect everything to be harder than it is so therefore it is. I'm not saying it's easy, and every exam is different, but I think Sims are a real chance to shine.
For example, I am awaiting my BEC score now. I am positive i got 3 of the sims 100% correct, but I am also positive that I completely bombed the fourth (it was just a tough question. It happens sometimes) so, my thought for this exam is if the sim I bombed was the pretest one, I will pass. But if it isn't, I probably failed because I probably did not do as well on the MCQs. I've never perceived an increase of hardness on the mcq testlets as some people mention. I'm not sure if that's because I really dont do well on them or if it's because I don't consider any one type of question harder than the next while taking the exam. They all seem hard to me.
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