I read on this board a while back, and my CFI has told me, that you should not score too well or too poorly on the FAA written exam. Too low means you didn't know enough and you'll be grilled on the oral portion of the checkride. Too high means you memorized all the questions and still don't know the stuff, and you'll be grilled on the oral portion on the checkride. Optimal is low 90 percent, give or take.
FAA exam is next week and I need to know -- truth or myth?
It's started by instructors to make students who did not score well feel better.
This is a very interesting question, especially to somebody like me who was preparing for the knowledge test till last Sunday, and is now preparing the oral exam and the checkride. I heard the same rumors from a couple of pilots, and always had the feeling that it's a lot more ego and psychology than facts. How come everybody recommends an optimal range of scores, and that happens to include the score they got? What a coincidence! Sounds a little bit like a-posteriori rationalization.
Anyway, I studied to get 100% and I got it. Of course, there's a lot of ego involved in that too. Am I overly competitive and fixate over grades? A psychologist could find out plenty wrong with me, but this is off topic. The topic is: what are the facts?
The facts I have to share are:
1) the only person who commented on my score AND is a CFI was my CFI, and he said: "great work - that will help you on your flight test".
That is a qualified answer that directly addresses the question, from an instructor who taught dozens of students;
2) getting perfect score is not a sign of just rote memorization. Yes, some questions on the test are idiotic (i.e., the FAR number that regulates preventative maintenance; the AC series numbers). But things have changed. FAA question banks have changed. You WILL encounter questions you have never seen before on topics you have never seen before. You'll have to reason your way out of it. If you just memorized answers, you will not get perfect score.
3) preparing for the last 10% took a disproportionate amount of time. It didn't take 10% more work... it took twice more work than preparing for 90%. Months of extra work. I independently researched aircraft maintenance, weather, radio engineering, flight envelopes, ATC procedures, and a lot more. I performed maintenance on the plane myself. I know that the material I am familiar with is *a lot* more than when I was ready to test for 90% score. That is worth something in practice, and it's not just being "book smart". Teaching yourself to chart courses, do weights and balance and solve wind problems without *any* margins for error must be worth something "in real life".
4) regarding the doctrine "if you got a couple questions wrong, they'll question on those... if you didn't, they'll question you on *everything*", I can't call it BS yet. I'll let you know what happens at the oral. But even if it were true, what's the big deal? I absolutely loved learning about aviation, and all the CFIs and examiners I met so far are very excited when they meet students who are truly dedicated and passionate. If my oral exam lasts twice than usual, what's the big deal? Is flying about passion or is it about minimization of effort? The best strategy to minimize effort is to keep your bum on your couch. That makes for the safest skies too.
All comments welcome, even if you just want to tell me I'm a pretentious a...... .
) put it on my head to cover my eyes and told me to fly straight and level. After 30 - 45 seconds he pulled the map off my head. I was in a 45 degree bank and diving for the dirt. He calmly said, "Let's work on unusual attitude recover now." 
I learn a lot that day. Use the experience to learn. 
