I was just thinking about this today - I write everything originally too, but then I research as well because inevitably some minor detail strikes me that leads onto another detail and before long these small bits add up and deepen the story. Occasionally I allude to events, names or facts that most readers ignore but I feel it works on the subconscious level and contributes to the ambiance or the sense of verisimilitude ( sorry for the big word!) Good post, michelle!