absolutely it does. you can bet that when this guy dies, there's going to be a bunch of behavioural scientists aching to pick apart his brain and see what's going on, and i can also guarantee that when he starts his psych evaluations, he'll be completely shut down and they won't get anything from him.
my point is that your comment is true for every family member or close friend of a murderer who can sit back, be honest with themselves and say: "oh, yeah... i thought he was kind of weird. i noticed some odd behaviour."