Regarding 3 lane highways...we had one that went 50 miles or more and of course the amount of head on crashes in the middle lane was terrifically high. And yes there were Burma Shave signs usually along farm land frontage...I have thought that probably the farmers got a pittance for the use of their land???? And I know 50 mph was FAST! When I started driving my Dad would look at the windshield and say...kidding me...that he saw 50mph bugs! on it! All these experiences were in mid Indiana in the 30's and 40's.