As per dictionary.com, parallax means "the apparent displacement of an observed object due to a change in the position of the observer." This word does fit quite well, does it not, when we speak about performance and risk?
I have written about performance from a matter of perspective. That is, depending on one's perspective, you may see performance differently or more importantly, have different requirements when measuring performance. The same applies to risk. Parallax is yet another way to view these phenomena, where depending on where one is standing, they are seeing things differently.
p.s., as for "parallaxical," I made that word up...but it works, does it not?