I can actually relate to many types of people... but only if I already contain part of their pattern.
I.e., I've got a bunch of past experiences and frameworks built on those experiences in my head, so I can overlay those fragments and patterns on the information I'm receiving from others, and if there's a match, then I can match up with them.
However, there are some types of people I just have a lot of trouble with, and further from NT style thinking, the harder it does get. For example, with my two INxx kids, I "get" them really well and can identify with them, although with my INFJ daughter, there's some ambiguity.
I can intellectually "model" the process by which my ESFP kid evaluates and acts on information, but it's not really something I can identify with, and I have to try very consciously and invest energy in working through things in his frame of mind -- it's alien to me. Nor can I extrapolate easily within his approach to life, whereas for other types, as long as I can get into their heads, I can extrapolate fairly well.
The parallel to this with fields of study is that when you really understand something, you can build off of it because you grasp the inner workings and how it fits together; obviously I don't really truly "grasp" how he works yet, because while I can predict to some degree how he will respond, I have no clue why he doesn't proceed differently much of the time and how he justifies doing things the way he does them.
EDIT: ... of course, if we want to talk emotional connection rather than mental/intuitive connect, it's even worse. Intuition is more my pathway than the emotional. My emotions tend to be more philanthropic than specific, and they are still built on (for example): (1) She says she feels like <this>, (2) I was in a situation like that once and felt like <this>, and (3) thus if she is feeling like I was feeling at that time, now I understand what she is likely feeling and can respond to her like <this>. Or I intuit how I would feel in that situation, try to tweak it based on what I know of her personality, then act accordingly.