I've been trying to think about the difference between conscious(mental) and subconscious(vital) strengths and weakness. This is something I came up with that seems to be an easy and applicable way of thinking about it.
Our base is strong, so our suggestive is weak.
Our polr is weak, so our demonstrative is strong.
This is over-simplified, so I'll explain what I mean.
In focusing so much on our base, we neglect the opposite realm of awareness(DS). For example, Te base are so focused on how tasks are accomplished and doing things effectively or the best way, that they neglect the human factor. I think a great example of this is scientific management which gave rise to the human relations movement shortly after to give balance to the extremely mechanical approach of scientific management.
>>basically scientific management treated humans like machines to optimize tasks to make them as efficient as possible. The human relations movement introduced the concept of how people have certain needs and that you have to look beyond their physical capabilities.<<
Now the difference with Te-demonstratives is that they are not consciously focused on material workings of their environment, but they end up focusing on it anyway subconsciously. So what is happening is that since they are so unaware of peoples attitudes and sentiments that everything begins to seem mechanical.
So in other words.. ExTj is so focused on Te that they neglect Fi. ExTp, otoh, is so negligent of Fi that they end up focusing on Te.
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For other elements it might play out like this:
Fi-base is so focused on the subjectivity of people and their attitudes and sentiments that they become unaware of how they function in the external sense.
Fi-demo is so unaware of the mechanical functioning of the real world that they begin to personify everything and see most things as subjective.
Si-base so focused on the details of everyday life that they miss bigger ideas and concepts.
Si-Demo is so unaware of bigger ideas and concepts that they begin on focus on the everyday unimportant details.
Ne-base are so focused on the bigger idea of things that they begin to lose sight of the minute details of everyday life.
Ne-demo are so unaware of the details of everyday life that they begin to generalize everything and see everything more idealistically.
Ni-base are so focused on how the events occurring fit into the flow of time that they begin to lose sight of the immediate moment.
Ni-demo are so unaware of the immediate moment that it begins to seem like it blurs into the events moving from past to future.
Se-base are so focused on the moment that they lose sight of how things lead to this moment and what the moment means for the future.
Se-demonstrative are so unaware of the cause-effect relationship of events in time that they just focus on what they can control in their immediate situation.
I'm not sure about the Fe/Ti relationship.
Ti-base are so focused on their thoughts of a situation that they begin to lose track of their human reactions and emotionality.
Ti-demo are so unaware of their emotionality and natural human reactions that they only focus only on their logical thoughts of things.
Fe-base are so focused on peoples emotionality and interactions that they lose sight of more objective interpretations of situations.
Fe-demo are so unaware of objective and impartial outlooks on things that they just act according to their natural human instincts.
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You begin to see that people's psyche unintentionally neglect their DS and their HA to a lesser degree which is why they accept help with it. Meanwhile their psyche intentionally neglects their polr in favor of their creative and role in favor of their base, and so they want to ignore it. In neglecting their super-ego, they become subconsciously oriented around their Id, but this is unintentional. So, while they are aware of it, they really want nothing to do with it unless it has something to do with the ego.
We intentionally focus on the ego and neglect the super-ego.
We unintentionally neglect the super-Id and focus on the Id.
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Another thought I had was about the relationship between the base and role functions. Many people regard them as total opposites. I disagree. Imo, total opposites are the relationship between dual elements (i.e. Se/Ni) for the reasons that I demonstrated above. Elements like Te and Fe are not total opposites. The are actually very similar and probably more so than any other elements (e.g. Je, Pi, Ji, and Pe are most similar). They are just different ways of looking at or approaching the same basic thing. This is why we are decently aware of our role when compared to our DS. If Se and Ne were complete opposites why is that ESxp's fixation on Se doesn't lead to Ne being as weak as their PoLR or DS?