Keegan has his critics. But if you read the book, Keegan puts forward Hitler as a fake commander, someone who put on a show of strutting in uniform but could not actually command. The most memorable incident is drawn from Hitler's office records. He is sitting around with several secretaries in attendance, going on at length about art and opera. He's told his generals on the eastern front not to retreat, but as the Stalingrad debacle becomes worse and worse and they are asking, over and over, well, what then are your orders? they get no reply from him. He has no idea what to tell them. He's letting them die.