I agree with Ron. There is nothing the examiner could tell a caller that has not been posted to the website. Other than quote some rules and regulations I don’t think even an expert would gain anymore knowledge than is publicly available. The examiner at the USPTO is the equivalent to a federal judge in the judicial branch. I you search though patent law I am sure there are some regulations he or she must adhere to. By applying common sense I would guess one would be not to divulge any non-public information. IMO