The reason I included both tags is that the `surface=compacted` reveals a process, while the `compacted=crushed_limestone` refers to a material.    The combination of material and process gives more information than either alone.  Regardless, surface=compacted is correct and more commonly used.  It is also important for routers to know that condition.

Would you feel better if I used a different tag, such as`compacted:material` to indicate that the compacted material is crushed_limestone?
