One I recall is when Eliezer was talking with the 48 Laws of Power guy on Bloggingheads.tv. He kept using the same analogy over and over, when the other guy clearly didn't get it. Eliezer has said he's specifically bad at coming up with good analogies on the spot.

Personally, I enjoy finding the proper path to bridge inferential gaps, and am quite good at it in person. I've thought a 'translation service' like the one Will recommends would be highly beneficial in such debates, but only with very skilled translators.