Maybe a slight tangent, but I've always chuckled at Kevin Rowland's (Dexy's Midnight Runners) withering put-down of Mick Hucknall's appearance: "If I had a dog with a face like that, I'd shave its a**e and teach it to walk backwards."
Harsh, but fair - although given his subsequent fame and...
Many, many, years ago, I had an argument with a neighbour.
As I was clearly winning, they huffed "You're the rudest person I've ever met."
To which I instantly replied: "Flattery will get you nowhere."