I know this thread is old but any more tailbone suggestions....
Still striking out. Bike in the shop now. Got rearended in a parking lot. Back crack Dr. says I need a soft seat. I saw one of the russel day long road sofas advertised that it "relieves tailbone pressure" . It looked comfy though. problem is I would like to try 'em out. Don't want to get stuck with a $500 +/- seat . I am beginning to think it is the vibration being transmitted thru the seat. Going to experiment when I get the bike back.