Question from a parent- Jan 26th SAT

<p>My son took the SAT as an 8th grader. He scored 690 Writing, 680 CR and 600 math. I had him work through some BB tests in preparation. Now he is a junior and I had him do test 2 math section in the Blue Book today to gauge his math growth. I just checked his answers and he was perfect except he left one blank. I asked him what was up with the blank question and he said he had no clue how to solve that one question.....My question is this, if my son happened to do that same test 3 years ago would his score today of ~780 be accurate. Not sure if one can remember the steps in solving the math section etc. I understand this may be a stupid question but I had to throw it out there. Math has always been his weakest subject in school. I'm not expecting him to miss any/many of the CR and Writing sections. These sections come natural to him. Thanks in advance for any feedback.</p>