Great post. Sounds like what I do during user interviews:
I told them that my secret to getting people to talk boils down to three words: "tell me more". Sometimes I'll provide additional directions, like "tell me more about what happens after the email arrives", but the basic concept is still the same. It's a short prompt to get someone to add in more details or to give clarification. Then I can use this additional information to ask additional questions, get feedback from others, or be able to ensure that what I think that I've heard is complete and correct.
Great researchers use short phrases or silence during a conversation to get more information out of end users. If find this to be my favorite part of the conversation. The key is listening, not talking.