The code is open source and patches are welcome, but I’d strongly recommend discussion first.
Overriding is the easy, trivial option. But when I wrote the import scripts, I didn’t like that. It would have destroyed legitimate edits. The MOT data is not perfect, and I’ve confirmed this on multiple occasions.
My basic premise was that the vast majority of OSM edits are good edits that improve the dataset. So, when an OSM editor moves a bus stop to the other side of the road, or deletes a stop, or adds a missing stop, it probably means MOT has it wrong. Every such change makes the OSM data a tiny bit better than MOT data.
If we mirror the MOT data as-is and override all mapper data, we get an identical dataset. If we incorporate mapper data, we get an enhanced, superior dataset.
At least that’s the theory. In practice, I’ve observed certain kinds of edits users degrade the data unintentionally. And I am considering an update.
Namely:
- Unintentionally moving the bus stops a tiny distance (<3m) while editing something unrelated. Creating needless differences with MOT.
- Renaming bus stops. I now believe that even if there’s a typo or an incorrect name in the MOT set, it should remain as-is, because it is the name used by all other navigation apps and it’s the name used in the bus speaker systems, and it’s likely the name on the physical bus stopsign. Names should be fixed MOT-side.
The update would override osm-side name edits or movements smaller than 3 (maybe 5) meters, but would retain other user edits.