Matthew Yglesias calls the under-construction Washington DC streetcar "the worst transit project in America," because it will run slowly, duplicate the service of a bus line, and supposedly slow that bus line down.
Yglesias is like a lot of mainstream thinkers who can't get their head around streetcars. They move slowly! They clog the streets! They are therefore a fad and a boondoggle! No doubt Yglesias, if he had been alive in the 1940s, would have been leading the public charge to get rid of them.
Now they are coming back, and that's crazy-making for those who think that the only purpose of mass transit is to move people at high speed. Streetcars are slow and expensive, and yet people keep building the darn things.
He goes wrong in failing to connect development and transportation. It's a form of tunnel-vision that is blind to Place Mobility.