My implicit assumption was: the route relation has an ordered list of ways and the start of the first way is the start of the route and the end of the last way is the end of the route. (the start/end of the way has is the node not connected to the next way/previous way in the relation).

My implicit assumption was: the route relation has an ordered list of ways and the start of the first way is the start of the route and the end of the last way is the end of the route. (the start/end of the way has is the node not connected to the next way/previous way in the relation).