Didn't post before, because looks like link farming, but http://test.thirtytwomachine.com . If I remove the inline `data:image` files, pagespeed doesn't error out anymore. When I hit this problem, I found other people getting this exact behavior according to their online posts. Nuke the inline svg and pagespeed works again.
Also, the error message is a bummer. "An error occurred while fetching or analyzing the page". If you told me some parser state in the error, at least I could feed that back to you guys, even though it'd confuse a great many web developers.