I suspect other INFJs have difficulty verbally expressing what their brain knows within the span of a short moment.Any other INFJs experienced a similar problem or am I just...[??]
But consider this. If you didn't do what you do (pick up the emotional clues), do you think being merely told about it instead of having experienced it would be adequate? I think the gap between the theory and the practice, even if the theory accurately represents it, is a... a world apart, shall we say?
Imagine if you lived in a world that didn't pick any emotional clues, and then a visitor from outside it tried to describe a world of emotional clues to you. Even if they did a good job, that alone would hardly make you proficient or necessarily able to comprehend their meaning.
Or not.