A former co-worker had dubbed rubber ducking "The Elton Method" back in the 80's. He worked for a university data center where there was a guy named "Elton" who was a great listener. The guy never had the first clue what you were talking about, but he nodded obsequiously and scratched his chin thoughtfully saying, "Hmmm!". In the process of explaining the problem to him, you would realize how to solve it. We still call it "The Elton Method" and a truly great practitioner can use it with any old brick wall. Don't need an actual person.