I have driven quite a bit in Germany over the years from Hamburg all the way to Zurich (over 2 days) in one case. I personally have found the German road signage and autobahn to very easy to adapt to and navigate. Apart from all the traffic, especially up north, I find the road system superior and safer than the US. We do now have behind the wheel training here in the US and we have since I was I teenager and went for my license. I'm not sure how many hours it is these days but no matter in my case I've got almost 30 years of training without having had a single accident :)
As far as treating the autobahn like a race track, all I can say is I follow the rules. I go fast when it's okay and safe to go fast, I get out of the passing lane when I see someone coming up from behind, I keep my distance from other cars, really a lot of it is just common sense.
I only use cars as a way of getting from point A to point B. I don't use it for my own personal beer touring. I put the car away when I get to point B and walk the rest of the day.
Like I said before, I prefer to take the train most of the time but find renting a car a very useful and convenient option at the right time and right place. Oh well to each his own.