"On a separate point, while the Nazis had some crazy beliefs, they still excelled in a number of important areas." Agreed, but what I was saying was that none of these areas involved general intelligence, science, rationality or deliberative reasoning.

Hitler was known to go over his speeches in retrospect with Goebbels, and note which bits worked and which didn't, so he could make better speeches in future. I regard this as involving deliberative reasoning and general intelligence; there's even an element of the scientific method in it.