aristotle - 4:47 pm on Jul 30, 2013 (gmt 0)
thanks for the explanation. I was thinking that there might be some clue in the log entry to indicate that the visitor came from Google.
Thanks for the links to the articles. If I understand correctly, they're talking about mobile traffic. One article also says that encrypted search for logged-in users shows up as "not provided", but still is known to come from Google. I don't know enough to fully follow all of it, but the trend seems to be that less and less information is being provided, unfortunately.
As for outbound links, I agree with those who say that they probably aren't the problem. In fact, there's an old SEO theory that outbound links to related articles on authority sites actually help rankings.