Okay, this is weird. It used to be if you visited a site from domain-a.com and then visited it from domain-b.com that the referrer was reset from your first referrer (domain-a) to the most recent referrer (domain-b.com).
Now I'm finding that this doesn't happen UNLESS domain-b.com happens to be an organic search engine like Google. Referrers are getting stuck on the first referrer instead.
I'm not sure when this has changed, anyone else seeing this? We've tested it in multiple setups.