SBCE assumes that reasoning and communicating about sets of ideas leads to more robust, optimized systems and greater overall efficiency than working with one idea at a time, even though the individual steps may look inefficient.12 In theory, SBCE could be conducted with no back-tracking or redoing at all. In practice, the costs of eliminating all back-tracking could probably not be justified. But a focus on convergence, rather than on tweaking a good idea to optimize it, can dramatically reduce the amount of back-tracking in the process.