Well, he's talking about productivity. You seem to be in a good position to answer that question. Where were you more productive, in the open office, or in the cubicle?

However, a cubicle might not be the best comparison. A cubicle is not the same as an office with a door that closes. As the IBM example elsewhere in these comments said, not all cubicles provide the benefit. A minimum height of the walls being one requirement.