I think I figured it out: it makes physically more sense to express the XYZ primaries in terms of the primaries of the CFA. The best you can then do in the colors from the CFA to XYZ, is to minimize the error made. This is what is implemented in the pseudoinverse() function, as described here: http://www.sci.utah.edu/~gerig/CS6640-F2012/Materials/pseudoinverse-cis61009sl10.pdf
This is done by minimizing the squared error of an overconditioned system of equations.
I think I figured it out: it makes physically more sense to express the XYZ primaries in terms of the primaries of the CFA. The best you can then do in the colors from the CFA to XYZ, is to minimize the error made. This is what is implemented in the pseudoinverse() function, as described here:
http://www.sci.utah.edu/~gerig/CS6640-F2012/Materials/pseudoinverse-cis61009sl10.pdf
This is done by minimizing the squared error of an overconditioned system of equations.