|MadSci Network: Biophysics|
From my research, no.
It would appear that our eyes can stimulate a three color perception using only two colors; the classic example is superimposing  a projected monocromatic image using a red filter, where the image was taken with a red filter, and  a white light illuminated projection of the same image, but where the image was taken with a green filter. Although there is no blue light in the scenario, blue tinted objects appear to exhibit themselves in the combines projection.
The amazement comes about because we classically consider out eyes to have a 3 color system, where each color is vectorally orthogonal to each other. It would appear that there should be no way to tease out a third dimension of color when only two are combined, apparantly in a linear superposition.
However, in answering your question, it would appear that although this two color system can represent all hues, it cannot represent all permutations of attributes of otherwise naturally colored objects: "The two-color images lack a full range of values and chromas, but they do reproduce all hues." See http://www.greatreality.com/Color2Color.htm.
I do believe this would be a fatal impediment to throroughly replicating an rgb vector [color] sum value. It would appear that the primary color that is missing in the two color scheme constrains the total visual value of the object to a certain combination or function of the other colors. Ergo, a color system could not do so with the two color system.
Try the links in the MadSci Library for more information on Biophysics.