This is an example of traffic calming = island, we need only to draw one way and not two with several tag one it.

osm.org/go/0BOmSL3lB-?m=

On this picture (the link below), you can see the lanes (numbers of lanes forward/backward and turn lanes) the result in the software and the mark on the real road (it isn’t a trunk and motorway), so in the middle it’ isn’t a “guard_rail” so we can considered that like a “traffic_calming = island” (the road in the bottom is a bus way and we can’t turn on it probably we can use a relation with “no turn” on it)

http://i.imgur.com/qDHDy6b.png?1

Before changeset: http://imgur.com/d8bPCdY

After changeset http://imgur.com/aM64YF4