The gist is that infjs have an aptitude for mirroring, which doesn't necessarily mean they genuinely care for others. I think that's the post's definition of empathy and I agree to a degree, empathy has the element of sympathy in it by definition.
The most interesting part of the post, however, which supports the point they make very well, is the mechanisms of mirroring. And in this case it's assumption. Sometimes really intricate, with some infjs being able to read body language and nuances of behavior very well, the infamous ni stare, which then get filtered to distill the essence of a person. Or it can be as crude as, you drive without your seat belt on, therefore you're reckless, therefore you're a deadbeat, therefore you're Bad™.
I doubt most infjs believe they're Jesus on a lack dragon, with magical powers, unless they're having a psychotic break. However, an ni-se loop with Ti running in the background can have more complex concequences than being too nice and turning into a doormat (which I do hear a lot). Mirroring at an extreme degree can alienate you from others, thinking people are your friends when they're only fair weather friends of themselves (the image the infj projects), or thinking you have invested your time and energy, and even love perhaps, to people, when in reality you were locked up in your head.
