We present an analytically derived model for flow induced crystallization (FIC), based upon the recent Graham-Olmsted simulation. We use combinatorial techniques to calculate nucleation energy landscapes, which correctly predict simulation data. Applying both the analytic calculation and the simulation, we put forward a simple expression relating nucleation rate to polymer chain stretch. We also investigate bimodal blends, an important step to understanding polydisperse systems and eventually modeling industrial polymer melts. (C) 2010 Elsevier B.V. All rights reserved.