Thanks for the detailed post.
Like explained above the routing API works correctly.
Then the clients choose how to use the responses.
The app merges via’s successive instructions, because one instruction can be announced per location.
Now it announces via’s name. There was not a need to announce together the via’s turn instruction too.
So the suggestion is that all turn instructions should be visible and announced in navigation?
Regardless of waypoint type, its turn instruction should be announced (u-turns and continue).
Obviously we cannot fill the app with options, that will complicate further the development.
The “Settings | Routing | Waypoints in instructions” already complicates app maintenance.