I tend to find myself in the position Xander describes perhaps more so because of Ne being so dominant with me. Sometimes it compensates for itself by picking up very quickly when someone's not following, and finding other ways of putting things. But a lot of the time I find myself torn between giving people a bit of credit and talking freely, trusting them to understand, and trying to be more 'linear', and thereby having this awful feeling that I'm condescending, patronising and talking to them as though they were idiots.
My ISTJ friend is a member of MENSA, and yet the way I have to explain things to him in order for him to follow me and 'get it', feels to me like I'm talking to a three year old child, and it seems his mind is impossibly slow. If I hadn't seen him do The Times crossword in under 8 minutes, or advanced calculus for fun, before my very eyes, and if he didn't consistently wipe the floor with me at chess, I'd think he was stupid and that MENSA made a mistake.
When he explains things to me, I get very, very impatient and bored because he lingers over things, goes through in tedious stages that he could quite easily skip, because by the time he's said the first line I've already made it to the end of the explanation in my head, and it's excrutiating for me to sit there politely letting him go through the motions and pretending a big 'Aha!' when he reaches the end, as though I were in the dark right up to when he started to triumphantly bang his fist on the table and say "And that's why...!"