“Project 250’s backers have come up with an ambitious plan and a seductive set of renderings, showing a sleek, 21st-century velodrome that looks like a cross between a spaceship and a tidal wave. Not only do they maintain they can build this high-tech, enclosed arena with zero public dollars, but they also insist they can operate it as a for-profit venture. All they ask is that the city gift them a four-acre sliver of South Philadelphia’s FDR Park.”