It would be very helpful if Rhino has a dedicated command to extract the control polygon of the selected object(s). The new command could be named _MultiExtract (or simply expand the capability of the existing _ExtractControlPolygon command) and include the following Command line options to extract any combination of:
ControlPoints=Yes (extracts the control points)
ControlPolygonEdges=Yes (extracts lines representing the control polygon)
ControlPolygonMesh=Yes (extracts the control polygon as a mesh object)
Linetype=Dashed/Solid/others (only shows when the “ControlPolygonEdges” option is active; adds a custom linetype to the extracted lines of the control polygon)
Group=Yes (groups the output objects separately, i.e. one group for control points, another group for control polygon edges in case that both options are active)
DedicatedLayer=Yes (places the output objects into their own layer named “Extracted control polygons”)
Color=White (choose from several basic pre-set colours)
P.S. Also mentioned here: