It’s done in a friendly, offhand way all the time. People calling elucidator “'luci” comes to mind.
Spare me. Are you going to tell me with a straight face that you were being complimentary rather than derisive.
No, actually, he didn’t. He said the meaning of Obama’s comment would have been clear to a “mentally deficient turtle,” meaning you were not presenting an honest interpretation of those comments. I admit I also questioned how forthright you were being, but I think a fair reading of his comments show he was not comparing your intelligence to that of a turtle.