It's not about the materials being exactly alike, that doesn't matter. What does matter is recognizing that Capstaff's procedure is always a 2-color process, but a 2-color process is not always the Capstaff procedure... that's all I guess.
At any rate, I think what you're talking about is interesting and by all means you should carry on!
The hologram films/plates do offer a unique advantage, admittedly, being the only emulsions that are both transparent and sensitized to only red or green. This can make an easy bipack; just pop a yellow filter on and voila. That is brilliant. I guess I wasn't thinking about how to get the separations as much as what to do with them once we had them.
This probably isn't practicable, but how about this for a bipack?... 3 different elements, sandwiched together behind the lens in this order; a film coated with liquid light, a very thin yellow acetate sheet, and a sheet of ortho film. You'd get a blue record and a green record. Or substitute the yellow acetate for red, and the ortho for panchro; you get blue and red records.