I think that's a commonality but not so accurate to this particular test. School exams for example are designed for that exact purpose, but this is not a test of a persons knowledge, it's more a test of revelation.
My impression is that it's not meant to show me where I stand or how to improve, because personality is a natural thing that evolves through life and should not be subject to forced change because that results in unnatural and unhealthy behaviour.
This test states that one type is not better than another, they are just different, so I don't see how it has anything to do with discovering strengths or weaknesses.