In this paper we investigate a genie approach from proving outer bounds in
discrete memoryless interference channels. We define a new class of very weak
interference channels on which one expects that treating interference as noise
achieves the maximum sum-rate. In this class, we show that the Han-Kobayashi
region reduces to treating interference as noise (for the sum-rate) and we
develop a genie based outer bound that was optimal in the Gaussian very weak
interference regime. We investigate the optimality of such genie based outer
bounds in discrete memoryless settings.