The point of Rubber Ducking (or talking/praying to the Wooden Indian, to use an older phrase that is steeped in somewhat racist undertones so no longer generally used) is that it is an inanimate object that doesn't talk back. You still talk to it as if you were explaining to another person, so are forcing yourself to get your thoughts in order in a way that would make that possible, but actually talking to another person who is actively listening and actually asking questions is the next level.