thanks! that was causing the confusion, because in my view, to "go in the direction opposite of other traffic" sounded like an enforcement for the way direction.

Basically the street is like this - skipped sidewalks:

# car use(2 lanes): =========>
# bike use: <-----------
# bike use: ----------->

> <, denotes direction of move

daveemtb: the wiki page is kinda confusing... (I've read the talk page too).
If I tag it with cycleway=lane on a oneway residential street would it mean that the direction of cycling is the same as the highway? because, if so... then it's not true: you can cycle both ways on that line.
Also, opposite_lane doesn't help either: would that mean that you can go in the opposite way as the car traffic? Also, not true.

matclab: how would I do that?

Nope, but I guess ...almost half of it.