I agree with everything else you say, and your general thrust, but I was never able to find corroboration for this claim. There was an article back in the day that claimed this was true, but was not convincing.

It’s a detail. Saying dumbshit is not illegal anyway. War crimes are illegal. Bush should be in jail.

But I think it’s important for “our side” (that is, the side of the non-pathological liars) to be scrupulously accurate.