I'm often the only planner in a room full of engineers. In Baltimore, there seems to be an overwhelming preference for one way streets given how many of them exist - especially downtown. In school we learned that two way streets in dense areas improve business visibility, ease navigation (especially for tourists), and serve as built-in traffic calming. From an engineering persective it seems total traffic volume is often the only consideration when designating one ways.
Have any of you been successful in converting one ways to two ways? If so, what were the arguments that worked? How did businesses react to the proposed change? Any comments on long term impacts of a two way change?