Nothing two-faced or open to interpretation about it perhaps, but it's a totally irrelevant insult. What is significant in a discussion isn't whether we like somebody or not, it's whether we agree with them or not. We might think someone is a total bastard, and yet completely right, or that they are are lovely, and completely wrong.

Personal insults are about as in place as much as they would be in court id the prosecuting counsel ended his summing up by saying "and moreover my lord, the accused has bad breath".