I saw a presentation on OSM at SOTM.US. They measured the quality of OSM pre and post redaction by looking at the number of highway miles. It got me to wondering, can we get higher quality data by removing roads?
In the US, the "base map" was the now famous import of US census TIGER data. The Census bureau has mapped Forest Service logging roads and driveways, and they were imported as highway=residential. However, they quite often seem to be wrong. Consider some of the Oregon coast range, how much value a driveway adds or even where it belongs, and changing roads in the desert.
I suspect these roads were created then abandoned. The only way to know for sure is to go out there and survey them.
This got me to thinking that the map might actually be improved by removing ways. What do you think?