On the new-fangled adaptive SAT, there's even more reason to guess. You see, in adaptive testing, the questions presented to you are a function of your performance on earlier questions. That means that one additional correct answer in an early section can permit a whole range of scores that would have been inaccessible to an examinee who blew that answer. Does the adaptive SAT distinguish (for adaptive purposes) between wrong-guess mistakes and omitted-response mistakes? Perhaps someone will writeup the answer; if not, this definitely tips the balance further in favor of guessing if you can eliminate one or more distractors.