He completely understands that he needs only to sit very quietly, head cocked to signal listening-ness, while senator after senator offers long discursive rambling speeches. Only when he's perfectly certain that a question has been asked does he offer a reply; usually cogent and spare. Here's a man long accustomed to answering really hard questions from extremely smart people, suddenly faced with the almost-harder task of answering obvious questions from less-smart people. He finds himself standing in a batting cage with the pitching machine set way too slow.