Unfortunately, your explanation is entirely wrong... and you're attacking a "lies to children" simplification with your mention of "needs to run longer way around" bit.
But the same I found myself unable to pass by someone pushing "flat plane at an angle".
Fortunately my exams were open ended not "fill in the circle in answer sheet" so worst case I'd have written a more complete answer and fought it out.
Worrying about having to fight against "answer key" is part of why only one person (and only on a lark) took computer science on Matura exam in my class - which was CS-math-physics focused one