First, I'm relatively new and only edit in potlatch.
While adding relationship status to US:I-80 near the junction with US:I-99 (http://osm.org/go/ZcSP5Ip) I came across an arrangement I was unable to resolve.
I added the relation to one direction and scrolled to the end of the way. The next way on the carriageway did not have oneway, so I added it. When I did so, i got duplicate direction arrows on the way I had just added the relation to. Looking closer, I realized that I had two ways sharing nodes both representing one direction of interstate for that area.
When I attempted to delete the nodes of one of the ways, both were affected.
I-80 WB way 1:11844889
I-80 WB way 2:34932489
This carries across multiple counties and multiple way sections of I-80 in both directions.
Advise and recommendations greatly appreciated.