He did debriefings for higher ups in the Army. Basically his job was to stay up all night and watch late night news (then mostly CNN) and tell the Generals and Commanders what happened in the world while they were sleeping.
He debriefed Powell a few times. He said he was incredibly sharp - gifted basically. He would know what everyone was going to say before they said it, would know what was going to happen in the world before he was debriefed, but he was not a jerk about it.
He had the best description of him -- he said have a conversation with Colin Powell was like playing a soccer game two goals behind. You knew you were never going to catch up, you just did not want to embarass yourself.