RNP
Kenny,
No experience with other than on Oceanic, Class II Navigation where traffic is separated by manual position reports and the pilot is expected to fly at filed Mach or whatever asked.
I did operate B737-400 EFIS with RNP in the FMC but of course never used it and yes, from my limited knowledge, the FMC has inputs on each leg for the requested crossing time with a resulting calculation of required speed in order to comply. Also, as I seem to remember it will give the pilot while still on the ground the takeoff time in order to comply.