Check out this web page: THE BEST KEPT SECRET: WHY PEOPLE HAVE TO SQUAT DIFFERENTLY. It shows side-by-side comparisons of different hip structures. We are all not made the same. The page is written for showing how these different hip structures relate to different ways that people squat, but having seen tremendous differences in the strides of many runners, I think you can see how this applies to our sport as well. The comments are worth reading too!
Here are the latest images of my hip taken in the spring of 2013. I was standing straight for the images.
|my problem left hip|
|my hips tilt for some reason|