My primary argument has more to do with the relationship to Feeling. Is Pon Farr more like feeling in an INTP, or an INTJ? Which of these types is more comfortable with Feeling, and which character is more comfortable with Feeling?
Do INTJs ever explode like INTPs do? It doesn't look that way.
Yes, but (hopefully) not often. I would not use Pon Farr to judge the character's perspective on emotion. It seems like a rather extreme and largely physiological phenomenon that all male Vulcans would experience, much like the adrenaline rush of the "fight or flight" scenario, though stronger. Spock's reaction to the fact that he is experiencing that customary Vulcan event seems much more Fi. He sees it as a loss of control, causing him to betray himself and his values. I suspect the Fe-based response would focus more on trying to mitigate its impact on others, or even what others would think of the affected person.
I think in general INTJs wrestle with feeling, emotion, and values more because the related function is internally directed and tert rather than inf. Most of this usually seems to be under the radar for INTPs, until, as you mention, it all surfaces and they explode. Their values (priorities, right/wrong) seem to come more from the Ti/Si combination, culling past experiences for what makes logical sense, which often entails reassembling existing components in new and unique ways (Ne). Not sure how Fe plays out in this. Often it seems like an afterthought: the INTP remembers, "oh, yes - I should ask the group whether they agree with this".
while spock might seem SJish by human terms, in Vulcan terms he's practically a rebel without cause, a man living on the edge, choosing to live a risky & dangerous lifestyle among wild, uncivilized animals (a.k.a. humans), and worst of all - he even takes 'em seriously, like actually considering what they say as possible valid points. he's full of the crazies!
and why not a feeler? in the land of the heartless maximum utility paradigm, the man who will shed a tear openly admit to having a negative association for the loss of his loved ones entire civilization is clearly a bleeding-heart wuss.
It is the sort of choices your first paragraph describes that illustrate what I called the irreverence in Spock's actions. He doesn't do what is expected of him, and never has. As for your second point, I think tert Fi is more than sufficient for such a reaction. (Would MBTI apply to Vulcans without human ancestry??)
