User blog comment:XXIsonXx/Sky-Line Info/@comment-939754-20100926000656

You notice how odd the shapes are of the skyline? And all those green lights and joints on it? I've been assuming that's all meant to give the structures flexibility. If too much pressure is put on it, it breaks, but they must have a system to make them fly back.

Although the buildings may move freely, that does not mean they don't have a system to keep them from colliding. The bell tower was a structural failure.