Mark, I will dispute the assertion that cross-streets are harder to place on single-line maps.
If I use a 2pt line for the main course lines, I then create cross-streets at a thickness of 1pt. I put the cross-street name perpendicular to the course, and it is there. I only place cross-streets that are close to the split locations, to keep the map less-cluttered. Example
I agree that single-line maps can be useful, but I also think there are times when the street-width maps are useful, also. If someone clearly states that runners have full use of the road (indicated on different sections of the map, accordingly), I don't think an arrow down the middle of the "curbed" road line is any problem. Example Each course needs to be evaluated on its own, and mapped according to its need. One method does not fit all maps.