Methods and systems for optimizing and/or designing integrated circuits. One exemplary method includes routing, as part of a process of designing an integrated circuit (IC), connections on a representation of the IC using a first set of wiring resources and marking wiring resources as used once the wiring resources within the first set have been used for routing and routing, using a second set of wiring resources in the representation, connections on the IC without checking whether wiring resources within the second set have been previously used to route connections, wherein wiring resources in the second set differ, on average, in physical size, from wiring resources in the first set. Other methods and systems for optimizing and/or designing ICs are also described, and machine-readable media containing executable program instructions which cause systems to perform one or more of these methods are also described.