I think what confuses people is sensing types (especially SFs) also report instinctive impressions, and they may think this is intuition because they may see them as patterns in experience. But what I notice is they almost always explain these by recalling concrete data (ie when SFs sense things about people, they really sense these things. They recall body language or something else they picked up with their senses & they compare it to impressions of other things they have sensed before and collective meanings (Si+ Fe) or they experience it in the immediate context along with an inner experience which informs them of the general human condition (Se + Fi).... The emotional aspect of Feeling and Sensing creates a system of experience and interpretation that can feel like "just knowing". I agree that the big tip-off of an N type is the difficulty in referencing concrete experience to back stuff up. Because we were focused on the "pattern", any concrete data is hard to recall (can't remember what you didn't study).