I notice that direction instructions are often duplicated as the route changes very slightly, example
you can see a series of 15 instructions one after the other all saying the same " Keep right onto M1",
is there anyway that duplicates like this can be combined into a single instruction ?
the instruction generation is handled within the GraphHopper core library that we use as the base for our routing. We experimented a bit in the past with trying to merge instructions together but it is a lot more difficult than it sounds as you need to make sure that an important instruction isnt missed off. Looking at your example it is definitely something that can be improved on. It might be wroth creating an issue on the openrouteservice GitHub (https://github.com/GIScience/openrouteservice) repository with this example and then the developers can see if it is something that can be done in our code or if it is something that GraphHopper would need to address
Many thanks for your reply and comments.