I think this is somewhat true with respect to discouragement when you are practicing a skill and getting good at it, such as learning to play a musical instrument. You generally develop skills and expertise in limited domains because of practice.
However, the flip side of knowing that you accomplish some things very easily because of your high intelligence also means that, from a conceptual point of view, if it can be understood by somebody else that means that you should also be able to understand it.
Also, if other people don't understand it, it doesn't mean that you aren't going to be able to understand it. It might take you a few minutes to unlock the problem where others find it extremely difficult.
