INFP. Yep, totally applies. You and I would drive each other nuts if forced to work together. You because you're too cut and dry, and me because I'm too altruistic. You can make snap decisions and come off as stuck up, and I procrastinate and come off as too shy to be of any social use.
Yes. I am also INTJ. Yes. Application depends on various other considerations, provided, the person meets the requirements of being Introverted intuitive Thinking Judging - INTJ (Introverted Intuition with Extroverted Thinking).
If you are not still convinced, please again explain the exact point where you are getting confused.