mmm.

ok, then i think i'll be more explicit about my comment.  as much as i wanted to verify (and i'm thankful to bagginsbill for doing so), i was also hoping to point something out.  a lot of the time i see all sorts of questions about how to vary bagginsbill's work when he's already posted either a material or equation.  and there seems to be a basic principle people are missing.

whenever a function is defined by a variable, or a node has certain input, you can always fill it with whatever you want.  just the same way you can make diffuse color any mixture of nodes you want, you can make any input any mixture of  nodes you want.  if someone says to use an equation f(x), x can be anything.  just because the examples provided use numbers, that doesn't mean that's all you can use.  you can make it a number, a color, an image map, etc.  

the only issue is if the new input makes the equation go crazy (become undefined, produce output that makes other parts of the material become undefined, etc.).  for instance, the nylon equations are designed to work with values from 0 to 1 for opacity and density.  so you don't want to offset your displacement map to indent (be negative), and then use the same output for density and opacity.  you want to apply the map to the opacity and density, then adjust it for displacement. 

don't get me wrong; i know lots of effects are difficult.  but if you want to apply a known control to parameters that have already been defined, it's easy: just use Matmatic to give the parameters the definitions you want or take the nodes you want and plug them into the appropriate inputs set to values of 1 or white.  also, it's easier to focus on the general behavior of the function than to think about what it does given specific input.  it's generally better to think about the whole set of valid input rather than the infinite possibilities that make up the set.  and 9 times out of 10,  bagginsbill normalizes his parameters to work from 0 to 1.