One thing that's been bothering me is that most people's cognitive functions don't really seem to fit their Myers Briggs type. While you would expect the norm to be something close to the way they're listed, I usually see a hierarchy of someone who has taken the cognitive functions test that does not fit the profile.
For example, the list for an INTP would go:
Ti Ne Si Fe Te Ni Se Fi
but most INTPs have something like:
Ti Ne Te Si Ni Se Fe Fi
Why is that? Does the list of functions not really work? Does the test look only for preference and not ability, and if so, are they really that different? Am I just seeing a lot of outliers for some reason?
The thing is, MBTI only tests for dichotomies normally, and often the actual function orders don't quite line up with what you'd theoretically expect. Usually the first two are on, but even that's not a given. The strongest Extraverted function (or Introverted function for an Extravert), should match the theoretical Auxiliary, though.
Now, let me give you a few examples to explain how typing works under odd circumstances:
Here's one possible functional order for an INFJ:
Ni > Ti > Fe > Ne=Si > Te=Se > Fi
Despite the fact that Fe is actually tertiary in strength, this person is still an INFJ because Fe is still their strongest Extraverted function, and Ti isn't too much of an anomaly considering it's Tertiary.
You could also have an INFJ with this order:
Ni > Ne > Fe > Fi > Ti=Te > Se=Si
Here's where the fun begins. I'm going to show you just how little it really takes to "change" someone's type.
Ni > Ti > Ne > Fe=Si > Se=Te > Fi
The above person would be an INTP, despite the strong Ni, because the strongest I/E pair is Ti/Ne.
And this is an ENFP:
Ni > Ne > Fi > Fe > Ti=Te > Se=Si
So the moral of the story? Type when messing with functions is determined by the strongest pair of I/E functions that fit together. The rest influences behavior but is discarded due to the limitations of the framework.
Of course, if you so choose, you can type yourself by dichotomies and forget functions if there's a real dissonance and you relate better to a type you don't have the functions for. It's all quite subjective and personal. This is why you shouldn't seriously question someone's type. It really doesn't make enough sense to be taken seriously.