We have a redirect so we can measure traffic in aggregate (we don't track who clicks what) to refine our content over time. But.. I don't believe we get set as the referrer the way we do it (30x redirects). I believe this is why Twitter's t.co redirector DOES use a true "dummy page" as then they get the referral. It's something that might be worth trying though..
Nope, it's what Mailchimp, etc., do. All the outgoing links just fly through their server on the same hostname. We do the same with our hostname.
I have evidence that Google follows these links though, because if you link to a "bad" site even through a redirector, Google notices and will throw you into spam or say you're phishing, etc :-)