It is the same for our government test for immigration! If you had to ask a native the same questions that an immigrant needs to know to become a citizen, all of us natural born citizens would be deported!
Rest assured it is just the same here in Germany...

Actually I spend much time on a forum at delphiforums which is about learning German, and I work there as a tutor. There are so many things I need to teach people which I never thought twice about before, and which weren't even mentioned at any time during my university studies of German and English... I have to come up with rules constantly, rules you never find in any learner's grammar...

Robin