I have an X-rite 810 densitometer, which gives me RGB values, and a ColorMunki, which gives me Lab values. Thus, I can read the color values for the patches of a linearized 21-step grayscale and see how far a print is from some desired color.
It is not at all obvious how to use these values to increase or decrease cyan, magenta or yellow inks to achieve, for example, a neutral outcome. *Are* these values any more useful than simply eyeballing the print?
Myron