Erm... I'm no expert, however I'm uncertain I would consider MBTI knowledge, especially in terms of apriori or posteriori.
It is a theory a well thought out one,but a theory nonetheless.
INTP is a general classification based on the cognitive functions, but Ti is supposed to be dominate. Even so, there are some on this board who claim the are INTP with Ne as their dominate function. They are highly introverted, but their function order makes them out to be extroverts. In such a case, I'd suggest you don't take things in such a general level (the INTP title) and, instead focus on the functions themselves.
In your example, where S is dominate as opposed to N, I'd think they'd be considered xSxx.
MBTI is based on a set of rules that may or may not coincide with the true nature of a person's psyche. These set of rules are then applied to individuals for a person to further understand them. When this application is made, you must come to accept people are unique and the set of rules is imperfect. Until it is applied, it is just a set of rules or a theory.