This is a subject that has been on my mind a lot. It isn't trustworthy. Ne is such a selective analysis of people based on our biases. The data set is so limited - we pick and choose and judge based on a very particular set of information.
I have so much intuition, it's coming out of my ears. I've realized, however, that I've badly misinterpreted people in the past because I've emphasized certain qualities because I felt that they were more relevant than the totality.
We need to take a step back and analyze our intuitions.
I think our Ne works just fine. Picking, choosing and judging is Te our least developed cognitive function.
The 2nd letter is information gathering. The 3rd letter is decision making. Ne doesn't analyze people, it just gathers information.
INFP functions in order:
Fi - making decision about ourselves
Ne - gathering information about others
Si - information gathering about ourselves
Te - making decisions about others
I find Ne very reliable. I avoid people I get a bad feeling from. Ne soaks up information from body language, speech pattern and hundreds of little nuances that I don't consciously register. Fi tells me how I feel about myself. I don't decide about other people because that's unreliable. I decide how I feel? Do I feel comfortable? Do I feel uncomfortable?
I've got bad feelings about a few people in my life. I don't know why, but I didn't stick around to find out. The problem comes when we get a good feeling around someone.
Now here's the problem that I see with INFPs. Our Ne gives us a vibe about a person. Step 2, we decide we feel good around this person and we might even like them. But we don't know why?
Instead of taking time to find out objectively. INFPs project. We want to like this person so we project qualities on this person that has no basis in reality. We start liking the person we imagine instead of the person that is. And when that person's actions doesn't match what we projected, we feel betrayed.