Based on this thread, I am convinced that assessments can hinder one from determining their best-fit type. Myers-Briggs was adamant that introverted types in general are highly subjective, but generally know when they are creating a persona, however extraverts being too connected to the object can become confused with their true selves and their personas. Both are capable of skewing exams based on these reasons
Taking this into consideration, introverts being administered the Step II or similar tests will merely continue to test wrong. To alleviate this type of skewing the best assessments in my opinion, are those which takes the introvert out of that comfort zone and have to respond with objectivity. Hence any tests that one has to consider in interacting with their environment. After seven years of study in type, I have concluded that the assessments that work best for me forces me consider how I interact with my environment. As a result temperament tests allows me to determine my true core beliefs, and reading material that distinguishes my interaction style works. One thing that I had to realize is, as a thinking type (more specifically the Ti dominant type) I had to preclude from slicing and dicing and compartmentalize a theme, instead look at it as a whole.
On the other hand extraverts typically have problems with introspection, therefore will get better results from assessments like Step II, as long as they answer each question while being cognizant of how I am alone and not around other people or interacting with my environment. I think the worst test (and no means of providing any true results) would be the cognitive type tests. The personality is too fluid and we use all eight functions at any given time. What do you think?