Strange Intropections
In my observations everybody can express their shadow functions, but only at great psychic cost and for short time periods. Even then they'll usually resist it.
I kind of agree with that but I can't tell you at this point what kind of agreement I mean.*
I get your point though and have a few thoughts about that. First, the likelihood of playing the other side of the street is higher when a person is younger than older. As we mature we become more comfortable and adept at using our strengths, so will live in our first two function most or all of the time, with the other two in their proper place as support positions.
This is the statement that blows my mind ... at least until I calm down.
Wouldn't that depend on who one is? I, for example, am interested in all those functions (and am definitely older) and would be upset if any were denied me. I need a curve to express the difference between what you are saying and what I am saying. Picture a Bell curve. Now modify it so ... how do I say this? ... the standard deviation is (1) very small; (2) very large. No. That's not what I want to say. Try this:
Maybe I'm deluded and I'm not an INTP but some other sort of monster. Yet look at how I post. I love to think about stuff abstractly (Ti), then I post it here (Ne) in some manner of expression. I try to be aware of sensations to guide my living (Si) and I will try to be socially agreeable (Fe) but don't go out of my way.
Now to the others:
Te - I will look to external realities and check their logical use for examples to fit theory.
Fi - I have internal feelings and even though I don't give them much credit, I had better know which ones are wild or if I'm calm.
Se - What would happen if I weren't aware of my wife's likes and dislikes? Occasionally I try to see them out there (Se) and then put them in my memory (Si).
Ni - along with my Ti I have a vague intuition about where I'm going but I only use that as a starting point and then Ti takes over.
All this could give me INTJ qualities but you decide.
Now you may be more practical than I and not as philosophically inclined. So you might not want to bother much with six of those eight.
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*Here is a try. Being and thinking about something are two different things. What I am (and you) type-wise is what I'm most comfortable with. But this wouldn't stop me from thinking about ANYTHING. When I do, I BECOME what I'm thinking about. The ease and lack of stress is in the thinking. As soon as I leave thinking, I drop the state of being. If I think about Te Fi Se Ni as tools, I become those ... and then drop them ... fast.