  Complete Monte Carlo (MC) simulation of a neutrino experiment typically
involves the lengthy and CPU-intensive process of integrating models of
incoming neutrino fluxes, event generation, and detector setup. We describe a
fast, geometry-independent, GENIE-based system known as NuSmear which provides
preliminary simulation of energy smearing and angular smearing for
neutrino-nucleon interactions. We discuss NuSmear's simulation methodology,
explaining its calculation of reconstructed values through its model-based
resolution computation, smearing distributions, and particle detection
dependencies. We go on to validate NuSmear's performance as a fast simulation
system through a series of internal and external comparisons testing its
predictive accuracy and model-adherence. Finally, we briefly explore the
potential for future user-customization in NuSmear.
