On Episode 8 of Tea with BvP (here, edited down to 13 minutes), Bill made the claim that if Input drives the car of acquisition, Output is in the backseat. He went on to say that you could make Swain happy by saying that Output is riding shotgun, but still not in control.
Bill also said the following:
“One role of Output is to help people get more Input…when you make some kind of Output people can judge…people actually speak to you at the level they perceive you to be at, which gives you better Input for yourself.”