This deep-seated hunch when people refer to Ni sounds more like the hunch that SPs act on, meaning that Ni would be unconscious.
When Ni is dominant, it becomes an obsessive vision or goal -- Se is acted out not in the environment, but in the form of internal fantasy and contemplation (i.e., the images in your head).
Se dominance is sort of reversed; inferior Ni aids dominant Se, and so the person is able to follow physical impulses as they come up through Ni telling them unconsciously.
It's kind of hard to think of N as an unconscious function, since it is a function that depends on perceiving through the unconscious. I would say it's unconscious insofar that it's a random thinking process. Ne has a habit of blurting out a random insight, playing with it for a little while, and then forgetting it. Much in this same way, Se has a habit of being the sensationalist -- interested in breadth of physical experiences. By contrast, Ni will savor insights and visions and will play them out in their minds. Si will savor a depth of experience.
I think that actual comprehension of intuitions and sensations or of the environment, in general, has more to do with a judgment function, whose purpose is to bring meaning and usefulness of the intuitions and sensations. I think that introverted judgment functions are more interested in meaning of perceptions; Ti is more interested in the systematic meaning while Fi is more interested in the humanistic meaning. Likewise, extroverted judgment is more interested in usefulness; Te is more interested in systematic usefulness while Fe is more interested in humanistic usefulness.