Scripting: Change Colour Printer to Print Black Only by Default
Colour printers can often print in Black & White mode, where they approximate grey scales. This saves colour toner/ink where the print job doesn't require full colour. However colour printers are set to print colour by default and in some environments you may wish for printers to offer Black & White mode by default. This can be done by the Printing Preferences dialog for each printer but can also be done via login script without requiring elevated permissions.
NB. The reliability of this command is not high.