Having the lines sexed differently also allows one to, if one has slack (not bulkheaded), connect the two lines up together to help keep them clean (out of the dirt- if one doesn't have and or use caps); also eliminates chances of dead-heading. Eliminates having a separate small piece of coupled hose for such purpose.
I ordered my NX with three sets of rear remotes, in which case I'll be running my third-function from the rear: have all the bits except some hose protection.