Comments: Can a stoic Dungeon Master run a successful campaign if he doesn't seem to be putting any 'emotion' into it?
Part of what makes a Dungeon Master great is the ability to draw you as players into the imaginative world you are creating. If the Dungeon Master is too stoic, the game becomes more of a grind, somewhat like a video game. That may appeal to some and not to others.
I wouldn't care for a stoic Dungeon Master. There would be no immersion. It rapidly would devolve into pure roll playing. It would work fine for a group that only cares about combat and not the social aspect of the world.