My head is spinning. According to this post, +Matt Cutts says: "We do believe in the privacy. If users are logged into Google, they’re more likely to be doing a search that’s personal and they don’t want that to show up in the referrer."

That logic is completely reversed in my opinion. If I want to do something private, I would log out and/or use an incognito browser.

Why would anyone log in when doing something private? It would be like yelling your name before doing something you'd want to keep private. Please enlighten me.
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