I know that I've discussed things on this level with other writers, but I don't recall ever hearing Patterson talk this way in interviews.
Also, he's reading off a cue card. Keep an eye on the way he moves his eyes and head. Always from his left to his right, except when he goes down a line.
I like the discussion topic though. Why do killers kill in thriller novels? Love, money, or to cover up something else....I guess they're talking about an intentional homicide that went well or I would have thrown in "by accident."