As an INTP, INFJs are the recurrent type that can make me feel intellectually overwhelmed (and even then I am left with a sense of underestimation, among other things because you're not the type to bloat).
I do wonder, however: could it be just a matter of perception -- or your view of things, and how you communicate it, being so different to mine that it contrasts styles rather than tell us something about our capacities to comprehend?
The following may help in help in this analysis:
(1) How do you view your own intelligence relative to others?
(2) And do you think the opposite is true: that INTPs (or any other type) often get the intellectual upper-hand rather than the other way around? If so, that would confirm paragraph 2. But I can't be sure, so I'm asking...