Should I Try One More Attempt at SAT II Writing

<p>I am having this huge dilemma on the SAT II Writing test. I have already taken the test three times. My scores have been 640, 700, 680. My friend, who has read many books about the Ivy league admission procedure and was accepted into Wharton, told me about the AI and told me thatI was on the border line between a 6 and a 7. If I gain thirty more points on an SATII then I would be a 7 and have a 50% chance of acceptance. If I do not then I would be a 6 and have a 25% chance. He was using the “Dartmouth” AI scale. I do know the chance are not exact and that there are other things that are considered, but if this little small thing could really improve my chances by that much I really want to do it. I am only applying to two Ivy league schools: Brown and Yale. Also, I am applying to a joint-program between Columbia and Yale. I was just wondering if anyone could tell me if getting thirty points on one of these tests can really improve my chance of acceptance by 25%.</p>