"It's all observational. You watch people enough, you pick up certain things. Especially around here, where emotions tend to run high."

That is, perhaps, telling about his own personality; he's rather strongly implying that he understands emotional reactions from witnessing them in other people and putting the pieces together in his head, not from having his own emotional reactions. Maybe that's true. Maybe it's just another bluff, another layer of his well-practiced poker face -- after all, it's obvious that he does have emotions.