A question

A guy tells a joke. A listener doesn't laugh. The jokester comments that since he didnt understand the humor that the listener is not very bright.

Is this a valid and logical conclusion ?

I ask this because this one of the themes coming from the comments following the piece on rape jokes here


When I first read the first part of the piece, I was rather enraged that anyone could get humor out of rape. Then reading further then reading some of the comments I have my question above.

If we don't count our blessings
We are just wasting our time