@MapleSarahp interesting! I might give that a go, thank you :) The problem is very much psychological, so tackling it with something psychological is a great idea. Thanks again!
I think that, for some reason, people downplay the psychological aspect of the test. A precipitous drop in one's score can certainly be due to those factors. I wish I had good advice about that, but I don't. Maybe others can chime in.