Tip - should we redesign our bus network? and how?

When planners develop proposals for redesigning a bus network, how do they do it? And when is it necessary? This morning on a professional discussion forum, someone asked how to manage the impacts of a Bus Rapid Transit (BRT) project on the existing network. Introduction of a new rapid transit service -- bus or rail -- is one of the common triggers for complete network redesign. I dashed off a quick response, and thought I'd expand on it here by talking about the network redesign process in general. In 20 years of doing bus network planning around the world, I've...