I don't see it. I see inferior Fe in bucket loads.But look around on INTPc. As long as it does not threaten their individual freedom (their Ti), INTPs tend to at least subscribe to the theory of Fe. Their observations wrt people are focused on the same things as Fe-doms and aux users as are their expectations wrt other people.
For example: hazing or ignoring newbs, bonding by attacking / excluding others rather than by finding positive common ground. Paranoia. Resistance to the imposition of any rules or standards. Antagonism towards authority. Lots of in-fighting and splitting off into exclusive cliques. Which splinter yet further because no one agrees on anything or someone feels slighted. An inability to come to constructive consensus on anything. Cults of personality. Witch-hunts. Sadistic humour. All kinds of drama which shatter, rather than promote, cohesion. (Meanwhile constantly complaining about that drama as if it were created by an external agency and not themselves.)
This is a perversion of extroverted feeling, not a manifestation of it. It is a distorted projection - as all functions which remain unconscious (I.e. inferior) must be. These things are fostered/fester at INTPc because it is the rejection of tradition/community (Si/Fe) that leads (damaged) INTPs to congregate there. They are bound together by the things they hate in common. They don't understand that what they really hate is a projection.
Therefore to suggest that INTP "social protocols" are informed by Si/Fe, is to misunderstand completely, what makes them tick. If such things exist at all, they are informed by an irrational rejection of anything Si/Fe.
If you think inferior Fe is watered-down Fe, it is simply because you have an inferior understanding of Fe. As well as of CF theory. "Inferior" in the Jungian sense does not mean anything approaching "watered-down". It's like the opposite, in fact. Unconscious "functions" often have stronger effects than conscious ones, but those effects are universally negative. "Watered down" more accurately describes the auxiliary manifestation of a function. Maybe do some reading outside of these forums (which are laden with lay misunderstandings of Jungian concepts).Watered-down cola is still cola. Even if it just has a hint of flavour. Which is what I meant I guess when I wrote that 'traditionally' (which again, is how it was meant).
To return to your analysis, no INTP is going to say "let's do it this way, because this is the way it has always been done" (Si) or "let's do it this way, because that's what the majority think is the right thing to do" (Fe). This is the direct opposite of what we do. We inherently mistrust established protocols and *must* test their limits. We are attracted to novelty. We are attracted to individuality and difference. We are persuaded only by the elegance and perfection of an idea, not by it's popularity or pedigree.
Ti is the opposite of Fe. Ne is the opposite of Si. They do not comfortably coexist, albeit in "watered-down" form.
Cognitive function theory, 101.