What is the basis behind the idea of Dom-Tert loops in Jung Function Theory? I have come across a theory relating to Jung Function Theory normally addressed as 'Dom-Tert' loops. I will briefly explain:

In Jung Function Theory, everyone has 4 of 16 functions. They split into Introverted/Extroverted, Sensing/Intuiting, and Thinking/Feeling. These, in broad strokes, aim to explain how people function in both Information Gathering (S/N) as well as Information Processing (T/F) and whether that has a subjective base, or an objective base (I/E).

This theory lays out that the first (or dominant) function and the third (or tertiary) function form a feedback loop, and the second function becomes underdeveloped. Below is an excerpt that hopefully gives an example of this at work (Myers Briggs notation is used as shorthand here):


  ENTP/ESFJ: Ne/Fe or Fe/Ne--Narcissistic Personality Disorder. This type often behaves impulsively and manipulatively, needing constant approval and admiration from others, running around investing in new thing after new thing, but never developing the self-confidence of a strong, subjective perspective. Fe used negatively may use its awareness of the cultural standards of others to intentionally offend or upset them, in order to service Ne's curiosity about the patterns in their responses. If Ti/Si were working properly, it would give the user a balancing sense of personal, subjective importance and free him of his dependence upon the adulation and unconditional acceptance of others. (Horrible example: Patrick Bateman from American Psycho.)


The crux being that everyone must use a balance of subjective and objective reasoning and perception to function correctly.

Now I realise that Jung Function theory is a favourite with armchair psychologists, and it's validity has been questioned, but I wanted to know if this theory is either a) expressed formally in any kind of Jung Function theory study, or b) if something like this imbalance leading to personality disorders exists in other psychological theories? 

Where does this idea come from? The writer of the above forum post doesn't seem to take credit for the idea or even lead us to what inspired them.
Has dom-ter loops theory been expressed formally in any kind of Jungian function theory study?
Based on a reasonably diverse search of Google Scholar, Web of Science and Scopus, I am concluding that dominant-tertiary loop theory seems to be an original proposal by the author of the forum post cited by the question author. It appears to be a theory which has not been peer reviewed, and which has not been validated within the theoretical Jungian or empirical psychology literature. Hence, it appears that the answer to your question A is no, dominant-tertiary loop theory has not been expressed formally in any kind of Jungian function theory study.
Can dom-ter loops explain personality disorders?
Because the theory is an original proposal which has not undergone peer review or scientific testing, we cannot say whether or to what extent it might help to explain the development or maintenance of personality disorders based on the available evidence (because there is none).
I would say it is not trivially wrong, in the sense that it doesn't appear to be internally inconsistent or inconsistent with Jungian theory in any egregious way, but at the same time, the lack of empirical evidence implies that we have no credible reason to believe that it explains anything at all. It is conceivable, but not probable, that dom-ter loops can explain personality disorders.
Does the idea exist in other personality theories?
Short answer: No.
Long answer: The more popular modern personality theories differ in fundamental ways from Jungian theory's ontology of the mind, and one of these differences in particular makes the existence of such a theoretical explanation of personality disorders unlikely to work out.
The reason is that psychodynamic theories assume personalities are a driving force underpinning behavior in a fundamentally dynamic (intrinsically time-dependent) way, while theories like the Big Five tend to be more static (time-independent) and descriptive than explanatory. That's why it's meaningful to talk about discrete types in Jungian theory, because it is conceivable that stable classes of patterns of behavior can emerge from interaction over time between these driving forces based on their relative contribution to determining behavior.
Static theories such as the Big Five or Cattell's 16PF do not have the same notion of intrinsic dynamics and interaction over time, so they can't lead to the same notion of discrete types. Instead of discrete types, the development of personality disorders is today mostly based on a statistical diathesis-stress model, which, for example, might hold that people who are high on neuroticism in the Big Five are statistically more likely to develop anxiety disorders given the right stressor. The statistical basis allows for more fine-grained analysis of interactions, but also makes them more difficult to understand and identify with.
Closing remarks
Satisfying negative answers are always difficult to write in the cognitive sciences, so I hope I have covered all the bases. Please let me know if I need to elaborate or explain on anything.