He's got the weight of the world on his shoulders so of course he is going to show signs of strain. If this means he jokes less than usual, so be it. He is obviously a man who is aware of the gravity of the situation and he is ultimately the one who is responsible for the troops. He sent them into battle, he's bound to worry about them. I'm grateful that he is interested in the war progress and the fate of our troops.
I don't think there is much in here about legacy building, per se. The article mentions the fact that there is no stenographer, nothing is taped, etc. Doesn't sound to me like a man obsessed with legacy building.
All in all my impression is of a man with an incredibly difficult job who is managing it and handling it. God bless him.
God bless President Bush. Prayers that God keeps him strong.