Reading the two articles, I realize that amygdala controls the sense of fear. But I can hardly find a situation in which we can live without any fear. It is the fear that alerts us and restricts our crazy behavior and actions. Indeed, we need to be fearless when facing new adventures (e.g., bungee jumping), but we don't need to permanently remove the amygdala to do so.
I generate some hypotheses too! I suggest one's aggression trait may be associated to the degree of the activity in the cells of amydgala. Moreoever, modifying the amygdala may be a way to treat those who live in deep fear in their everyday life.