"Dark Knight" opens this weekend, and a lot of you are probably thinking about donning your own horns and cape and kicking a few local criminals in the balls. But be careful! A life of crime-fighting can only take you so far, before your knees give out and you get a concussion or something. Anyway, that's the premise of a (wacky!) new book by Paul Zehr, a professor of kinesiology and neuroscience at the University of Victoria. "Becoming Batman" doesn't come out until October but it's generated – if Prof. Zehr don't say so himself – a level of interest that's "through the roof." So what does "Becoming Batman" offer the would-be masked marauder? ...