Nearly every street in my town, and most highways in my state, are "contraflow": traffic on one side moves in one direction, and traffic on the other side of the street moves in the other direction. Sometimes there's a paint stripe separating the traffic, but sometimes there's not, and yet vehicles crossing center and hitting head-on is a very, very rare event.
But I wonder in the above example: How do they sign the intersections?
"One Way" would indicate to cross traffic that one need only scan for traffic in one direction. No "One Way" signs would indicate cars could turn down the street.