This week's Good Cycling Facility is a formerly one-way road in Delft (for all traffic, including cycling) that has recently been converted into a two-way cycle street, with only one-way flow for motor traffic.
A general principle is that streets should always two-way flow for cycling, and that one-way streets should be adapted, if necessary, to allow two-way cycling. This is precisely what the city of Delft has done, shortening trips for cycling, while retaining one-way flow for motor traffic.