For this thread's purposes, I am speaking of "function states" as you're representing them. Not only do I find this approach useful w/r to breaking my life into phases of stress, growth etc., it also rings true for what I'm experiencing right now. Which leads me to--
It might not have anything to do with a focused development of the tertiary initially, and in my case it didn't. My experiences led me to a point (now) where I see firsthand what I've been doing: coming to grips with my underdeveloped tertiary because I've felt I need to. Because the present circumstance requires it, because planning for the future in my present context pretty much requires a tertiary strengthening.
It is a symptom of immense stress or a challenged mental state in this case, because I'm finally being pushed to exert the less-consciously differentiated parts of my psyche to do better now and over the long-run. Most would call this an Ni-Ti loop--I'm not suggesting that Ti's overridden Ni, but rather that it's caused me to withdraw from use of Fe because it's been eating up more of my attention. We do diverge here if you think Ti can't possibly "jump to the auxiliary spot" in the sense of it experiencing more growth relative to Fe during times of stress, novelty, or hardship, which by definition would require use of a function or resources we're generally less comfortable with.
When Fe's not given the results you want, it'd be borderline insanity to keep repeating the same approach in the same circumstance it's already shown to've failed time and time again. This is exactly what's happened for me, and it's exactly why I do happen to think Ti is, by appearances anyway, closer to that auxiliary spot right now as far as where my conscious energies are being demanded more.
Yeah, you and I have a completely different approach to how the functions work together. My immediate question to you is, if everyone's in different phases of developing their non-dominant functions and we're only using one function state at a time, how do you approach the business of typing someone? How do you know you've typed yourself right? It seems like there are suddenly more than just 16 type combinations to juggle. How does a INFJ in the middle of developing their tertiary Ti differentiate from a run-of-the-mill INTP? Or an ISTJ with the same tertiary dilemma?
Also, what do you mean by "Fe not giving you the results you want." What kind of circumstances do you mean? Give me an example.
I personally have some misgivings about dominant-tertiary loops being something that is commonplace or necessary to the development of one function over another. It strikes me as more abnormal rather than typical psychological development. I personally think that what you're describing here sounds more like a good ol' expression of the inferior.
What happens when the processes already conscious and familiar to you (Ni-Fe-Ti-Se, by your count) fail? If Ti-Se are still to be considered conscious and familiar, what do we do when a circumstance requires resources that aren't quite so conscious or familiar? Where do we turn?
But see, it's not about the individual processes themselves, its the order they're used in. If INFJ cannot solve it's only problems, it heeds the call of its anima/animus and begins to behave as an unhealthy ESTP. ESTP is as opposite to INFJ as you can get. Barring some serious mental illness or experimentation with heavy drugs, I don't know how complex of a problem you'd have to warrant all your functions to change to their mirror ENFP functions, going from Ni -> Ne, Fe -> Fi Ti -> Te and Se--> Si. To me, that doesn't make any sense. Introverted intuition is a back left brain process, whereas extroverted intuition is a front right brain process. That's a complete 180. And having the entire function order flip over like that just strikes me as too "neat." You'd be a completely different person cognitively and very few people suffer such shocking trauma that they'd react to a situation by creating an alter.
Because raw data's nothing without interpretation? Ti provides an interpretational style that differs in critical, indeed, rival ways from Fe's. It provides logical structure and tests/checks for objective, impersonal criteria, with special attention to technical consistency rather than anthropocentric harmony, the latter being Fe's department.
I don't disagree that Ti 's interpretational style is rival to Fe, but they can and do work together as a function pair. F is holistic, T is linear. As long as one is introverted and the other is extroverted, they synthesize their findings. This is why I'm so confused by your Ni+Ti suggestion. I'm still wondering what on earth Ti would be able to productively do with Ni's observations beyond looping back on itself. Ni and Ti are both introverted functions which rely on a specified and localized conceptual context. The combination of the two just spells a continuous tumble down the rabbit hole. Perhaps an example of what the Ni+Ti process would look like and its conclusions would help me understand what you're getting at because the way I understand it, it's not all a process I would want to cultivate to rely on exclusively (as you suggested in your OP). If you're unhappy with the results of Ni+Fe, I can't imagine what kind of myopic, analysis-paralysis you'd encounter with Ni+Ti.
My other question regarding your take on theory is how you imagine a tertiary Ti learn to integrate with and compliment an extroverted auxiliary once the 'tertiary phase' was over. I always understood that the whole purpose of function development was teaching all the functions to work together and compliment their findings. If tertiary Ti develops by only synthesizing Ni findings (assuming it can do that without going nuts from second-guessing itself), how would it performed with information taken from a more global context?
It's actually unclear (in Psychological Types, anyway) whether Jung actually intended for this interpretation. A lot of Jung scholars are indeed of the opinion that, while he never outright says which I/E attitude the auxiliary is supposed to have (merely that it has to be judging if the dom. function is perception and vice versa), he might've even intended for pairings like Ni-Ti-Fe-Se to be the case instead of the contemporary Ni-Fe-Ti-Se model. At the very least, it's very difficult to extrapolate from his work that he truly believed the INFJ must be Ni-Fe; the least presumptuous interpretation would simply be that Jung viewed INFJs to be Ni-Jx, where x could well be either e or i.
Well, assuming that we do indeed understand what he means by I/E attitudes and how inferior and dominant functions work together and how all those are use to interpret the matrix of our reality and how we get feedback, then the no, the like-oriented pairs would not make sense
I'm finding this to be a very interesting discussion!
EDITED FOR CLARITY 
