While perfectionism may be a great trait in sports, on the job and in life, do not try to be perfect on the SAT. Only a very small percentage of all test takers will ever achieve the elusive 2400 score. For the rest of us, our mission is not to be perfect, but to answer as many questions correctly and in a timely manner without getting bogged down on an impossible question.
The SAT is a moderately timed test, you must work at an average pace. You do not need to be a speed reader, but you cannot stare at the page for several minutes either. For math, you do not have to solve every problem in 10 seconds, but you cannot spend 5 minutes calculating and crossing out, calculating and crossing out, etc., etc.
Perfectionists are loath to omit a question for fear they are giving up. Trust us, your life will not change and you will still get into a great university if you get over your perfectionism and learn to strategically omit the impossible questions.