Does anybody have any personal experience with score increases your final three weeks of preparation?
Yes. If everything falls in place, your score can rise greatly. I felt I had cleared the bump (consistent 700+) in the last two weeks of my prep. Things were beginning to "click." I began to breeze through the sentence correction, critical reasoning was making sense, and reading comp was becoming bearable.
I firmly believe that had I prepped for another week or two, I would have increased my score by at least 20 points. Unfortunately, the timing doesn't always work out. Imagine if we could just walk into the test center and test whenever we wanted?
Anyway, yes, when things are clicking, you'll see the questions in a new light. This happened to me in the last few weeks of my prep.