Cone Piezography used to be linearized and partitioned with the expensive and fairly complex rip Studio Print by ErgoSoft. That is still is probably the most precise platform for doing monochrome blends and splits and plenty of people still go that route for highly specialized set ups.
However, these days most of us are using Quad Tone Rip with the K7 inks. I have the K7 Carbon Sepia set up in a 9890 and it is by far the most beautiful, dimensional, and stable warm tone pigment workflow that I've ever seen. The Ardenburg test results done years ago shows this set to be as permanent as anything there is and I use it with the Canson papers that have pigment whiteners. From my drum scans of 100 iso 4x5 film these inks with Jon's custom curves made for QTR really capture everything I can see on the film. Same is true of the dslr work I do with them, nudes, landscapes, portraits and my still life work all look amazing with this many dilutions of gray.
I can use others too like Epson Vivid Magenta set out of Quad Tone Rip, or the Canon 8300 out of True Black and White, or the HPZ as an RGB device out of Lightroom or Photoshop, toned for very nice single hue prints. But it isn't the same as K7. If it were I wouldn't have a new 44" printer sitting over there with only one ink color in it. Is it worth it? It is to me and the people I do work for. I can and have matched the print color with some effort with all three color ink set ups but I can't duplicate that dimensionality of K7, I just can't.
john