I don’t know, but I used to.
One of the joys of writing a book like Summit is that you get to research stuff like that. One of the resulting temptations is to try to fit every last bit of research you did into the novel. You want to show off all the shiny pieces of geography and cuisine and cultural ephemera that you so laboriously picked up. It’s not hard to spot this in some novels. In some cases, you wonder if the author set a scene in a particular locale so that he could deduct a vacation as a business expense — I really went to Jamaica to get local color for my novel, not to lie on the beach.
The goal, of course, is to make the novel’s world come alive for the reader. Throwing in the names of Russian cigarettes and cars and subway stops helps, but of course there’s way more to it than that. The key is to get inside your characters and figure out how they interact with this world — not just what they smoke, but why they smoke.
Of course, you’re going to get some things wrong. I was told that Summit was extremely accurate in its depiction of the Soviet Union, but I had a character wearing the wrong kind of coat in one scene. How did that happen? I wrote down enough notes about Soviet clothing!
Does a lapse in verisimilitude matter? Not to the vast majority of readers, who have no way of telling, and are just going to take the author’s word for it. But it mattered to me. You want to do your job right.