<p>Yes, there's no point in retaking a 790 to get an 800. But I think it's worth it to retake a 740 to get a 790 or an 800. How do you know if you can or whether you should spend your Saturday morning doing better things? In my experiance, taking the practice tests from the official Subject Test book allowed me to compare my actual scores with the practice ones, and if they differed significantly (+/- 40-50 points?) I could make a more educated decision on whether to retake. </p>
<p>Just my two cents.</p>