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In NL no roads are imported. Many years ago the Dutch road network was imported from the AND database. In this database a road consisted of many segments (just like the Dutch National Road database (NWB)). One for each connection with an other road. All segments had an own AND id which was also imported in OSM at the time. Later on we realised these AND id’s were of no use at all and thus… were deleted from OSM. We also realised that we would never have roads split in so many segments if they were manually mapped. All these segments also have consequences for some data consumers. Nominatim returns all these segments if you search for a street in a city. (try Marianlaan Zwanenburg e.g.) and Carto shows a lot more street name labels when there are many segments.

It is also good to realise that not all segments were created by AND import. A lot were created for reasons unknown to me. Maybe an error in an editor. Or maybe a way was cut because only a part was surveyed and a mapper wanted to add a tag (e.g. surface=asphalt). When someone else later also adds this tag to the other part we end up with a split way for no reason at all. During the 90.000 combinations we’ve already made we’ve also seen many very small segments (often no more then 1 or 2 meters) that were very easy to miss when working on route relations.

As far as I know consensus in OSM is that highways are not split unless tags differ or when (route) relations requires us to do so. Also for consistency reasons in OSM it would be a good idea to combine ways. Also see this response in the Dutch forum regarding route relations.

For further information please also see this thread on the (old) Dutch forum.

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