itheenigma wrote:
Example - I saw somewhere that the probability of a PS question having 'D' or 'E' as the correct choice is higher than A/B/C.

That's wrong. I've looked at the answer choices to almost 1000 official questions, and each answer choice is correct equally often. A GMAC research report also says very clearly that they control for 'answer position' to ensure that a test taker using a 'always guess D' strategy will have no advantage over a test taker using a 'always guess B' strategy.

If you're down to two answer choices, and need to guess, the best advice I can give is to guess *quickly*. If you don't understand the question well enough to pick the right answer, and if extra time isn't likely to help you to work out which answer is correct, then spending any further time on the question is just wasting time. Beyond that, unless you understand the question well enough to prefer one answer to another, there's no guessing strategy you could plausibly use that would be helpful.