QTR-Quadtone RIP

Jon Cone places a premium on preserving shadow detail and opening the
    shadows, and tells you *never* to convert to the ICC, only
    to use it for soft-proofing.  But if you follow this workflow, you've got no (easy) 
    way to re-linearise the K7 curve.  You've got to pay $99.  Or develop a
    spreadsheet to hack the .quad file.

<sigh> And this is the part where all the stories end-up with a big "here be dragons!" sign. 

Brian, is there some reference some theoretical framework about the math involved, about the algorithm, something that would point out to the steps needed to linearize a K7 ink set? In other words, why is that everyone seems to be so afraid of the math involved in the linearization process? What's the catch? Are we talking incredible complex equation systems or something like that?