I hear what you're saying... deliberate misunderstandings are the
responsibility of those making them - I think I hear you also saying
that you're not responsible for stupidity either, and while I agree on
the face of it, I disagree that an intelligent person is somehow less
responsible for their own ability to communicate because their
'opponent' is working with a more limited understanding.
My point is merely that in any attempt to communicate, the
responsibility for success or failure belongs to those attempting to
do the deed... if you fail to communicate, the portion of
responsibility that is yours is still yours.
So what I mean is, if you intended to be denigrating you hit the mark,
and if you didn't intend to be denigrating you mis-communicated, and
either-or, your responsibility - or portion thereof - is your alone.
I hope that makes sense.

L.