I don't feel like you understood my previous post. The surface tag represents a condition of a surface.  The condition is the outcome of both a process and a material and that can vary.  surface=crushed_limestone is a material and doesn't represent the surface well.  as a sole tag surface=compacted is better.  

Adding additional information for the.surface is accepted for other surface tags, like stepping_stones and gravel, so I don't see why the same wouldn't be true for compacted.

