Functions op_Multiply and op_Addition for Matrix

I noticed the function op_Multiply and op_Addition for Rhino.Geometry-Matrix. But they are not working or documented. Are these placeholder for current version. Will they be available in Rhino 6?

Here is the Rhino 6 documentation: http://developer.rhino3d.com/api/RhinoCommon/html/M_Rhino_Geometry_Matrix_op_Addition.htm and http://developer.rhino3d.com/api/RhinoCommon/html/M_Rhino_Geometry_Matrix_op_Multiply.htm - these are implemented in v6.