This decision is one of the main questions I would like review on: technically, this is just a section of social history items and there can be N of them. In practice, it seems like the most important thing that goes here is smoking status (and often it's the only thing that goes here). So I was trying to weigh amongst:
1. parsing everything blindly, making it harder to distinguish smoking status as a special item
2. parsing everything but adding some special code to store smoking status separately from any other items found
3. what I did here (just pull out smoking status)