Dye-transfer matrix film is nothing but a carbon tissue with no pigment and the addition of silver-halides... basically. Then, thanks to a tanning developer the gelatin hardens in relation to the developed silver in a given area. In this respect, it is just like carbro; a process in which you take a carbon tissue and put it in contact with a typical silver-print (bromide) in the presence of potassium-ferricyanide (off the top of my head). The potassium-dichromate in your gelatin/carbon tissue and the bromide of the print interact and the gelatin is hardened, just as though it was hit with a strong UV light source. My point you ask? Well, you'd have to hunt down some old Kodak matrix film or make some of your own to do dye-transfer in this manner. But, a carbon tissue could be exposed in the typical manner, UV, and instead of doing a gelatin transfer, the gelatin could be imbibed with dye to make a sort of rag-tag dye-transfer print. Sure, tailor-made matrix films would be luxurious, but would this not be capable of creating a reasonable dye-transfer print? The gelatin relief images could then be re-used in the normal dye-transfer manner, to make any number of prints thereafter. This is the huge advantage of DT over tri-color carbon and the reason why it remained a viable commercial printing technique long after the other "assembly" techniques faded into obscurity. I see this as a solution to two problems; 1) the unavailability of dye-transfer materials and 2) the difficulties of making a tri-color carbon/carbro print; which is not as simple as using 3 pigments, due to reflection characteristics and a host of other things... or so I've been told. Plus, the enormous effort to make a one-and-done print.