I do sometimes use hard 47 deep blue versus 61 deep green glass filters under the lens for sake of split printing. I also have equally tight narrow band Blue and Green channels for my additive halogen colorheads, which can be varied to any intensity, including pure blue and pure green. Yellow and Magenta filters cannot do that; they always pass some white light too, no matter the so-called Grade value. But that's not necessarily a liability. For punching blue somewhat less aggressively, I keep on hand a simple 82B med blue conversion filter nearby, as well as medium green. There are all kinds of ways of doing it. Mix techniques if you wish. Whatever works, works.
I have no interest in getting hung up in the terminology. So much of this is subjective anyway. Specific VC papers respond in somewhat different manners than one another. But as long as one knows that Blue or Magenta increases contrast, and Green or Yellow decreases it, they're on the road.