I was listening to commentary on Marquez, and they were saying that he seems to pick a slow, innocous corner in practice and then hit it faster and faster until he falls off/has to save it with his knee and elbow, and then he knows exactly where the grip limit is for the rest of the weekend, given that tracks tend to have fairly uniform tarmac these days.
I also read in MCN a few years ago that he does a shittonne of yoga, which might help to explain his astounding lack of major injuries so far...