Unstable Surface Training

A few of the sites I frequent seem to be down on stability ball training and other forms of unstable surface training. Mostly it's shrugged off as "not functional" or "you get all the balance training you need just living." Personally, I find it useful, but I'm not a slave to it (or any other training modality). With that in mind, I was interested to read Art De Vany's take on Paul Chek ("simply put, he is among the best"), and in particular, this bit:

The idea is to work out on an unsteady surface to train your balance. But, the more important point (which I think you may find only Chek among trainers points out clearly) is to trigger unsteady states wherein the dorsal horn must quickly activate a response. The dorsal horn is down near the end of the spine and it is responsible for the extremely quick corrections that do not have time to go up the spinal cord to the brain and back down in time to make the correction. This tends to over ride learned, disfunctional neural patterns that come from protecting the lower spine from past injuries or poor patterns.

I know pretty much jack about Chek, and had never heard of the dorsal horn before (even now it sounds vaguely like the "five dollar shelf stretcher" the grocery store manager from my youth used to send new stockboys to the storeroom to find when they couldn't find room on the shelves on freight day) but having suffered back injuries in the past, I know it can happen in an instant on one off step, far quicker than your brain could ever brace for intentionally, so the notion of training the right corrective reflexes rings true to me.