The question bank used for the actual exams is now getting routinely updated and amended. I know a guy who is extremely highly qualified in the military who just used the question bank and was defeated completely by the trivia that was asked in a recent exam. He wasn't alone. Unfortunately I think you've got to learn the stuff (even though you will dump 90% of the knowledge later). The mandarins in Brussels have taken some dumb decisions on whatvto include in their gold-plated version of the actual ICAO syllabus. For example for PPL nav, why does the guy need to know about great circles?
Having been through process with licence in hand, but staying in, I'm happy to advise by PM. I have done rotary and nearly finished FW before changing my path.