The Topic Changer must alter the course of every conversation on which he embarks. He is the steer-master, the mis-leader, the bad driver on the road of interaction. At work, people stop inviting him to meetings; they know he will only "take them offline" while still "online". He is the one who aims squarely at the 'rat-hole'.
He cannot answer a question directly, but he is always glad to answer another question entirely. Is it raining outside? It may be, but it's interesting to note that cats do not like to get wet. Is the president an idiot? Possibly, and did you know that hunting licenses are not required in Wyoming? Someone starts talking about a hamburger and before they know it they find themselves listening about glaciers.
The Topic Changer can take any topic, any topic at all, and change it to literally any other topic. Usually he proceeds by links of association, but sometimes he'll just jump directly to the unrelated matter without making any connections at all. Associations are also loosely defined. Rain to wet to cats. That's two moves, and you can see how he gets there, but hamburgers to glaciers occurs with no moves whatsoever.
His partner in discourse is hopelessly lost, and trapped. They want to yell 'hey, dammit, we were talking about hamburgers, not glaciers!' but know from experience that this would only serve to move the conversation from glaciers to something else as completely irrelevant and uninteresting, so they might as well stay with glaciers. This global warming problem is really serious. The heater in my apartment is broken, and my landlord is such a dick. His wife makes the best cream pies. Have you ever gone for a bike ride down along the canal?