Passing exams and understanding a subject are two completely separated processes. The first will get you a signed document from your NAA, the latter will make you pass your first technical interview and hopefully give you a rough basic idea on how things work. But when things will go wrong in flight these laughable exams won't do anything to help you.
You'll save the day with what your flight instructor taught in that little Cessna a million years ago, what that funny TRI managed to write into your brain during your TR and what that rich plane builder wrote in the QRH. And luck. That's pretty much it.