Well fair enough, I could have been clearer, but I was hoping to pitch this to people that had a basic knowledge of control theory. On reflection, this is probably too small a group. So to explain; the situation is actually somewhat reversed to the impression you have come away with. In the continuous domain (I.e. analog feedback) our mathematical models as used are only for linear systems. So if you have a non-linear system or response, you find a linear portion and stay within that range. But non-linear is extremely important even in simple systems, for example a motor saturating. You can of course create a non-linear continuous feedback system, but you can't use Laplace to help you model it. In the discrete domain (digital feedback), the mathematics become very simple and although non-linearities still pose a challenge, their are many more tools in the chest for modelling these transitions. But in the world of engineering nobody bothers with even that, they just buy a PID controller and tinker with the three values. So what we end up with is a discrete controller over a strictly linear system. And you can see the appeal, the maths and modelling is extremely simple, and most people in the domain know how to do it. What has been happening in the last couple of decades is that miniaturisation of electronics is starting to make analog relevant again on the one hand (due to size, power efficiency, speed of response, and the fact that noise is less of an issue in these applications due to size), and on the other you are seeing the exploration of the "soft" and inherently non-linear properties of biological systems to perform the function of extremely complex control systems within the robotics arena. The problem has been that we have had no mathematical way of modelling this, but this article is describing a new approach. So yes, perhaps I got a little excited and left out a bunch of detail, but that's because there is just so much detail required. I just can't understand why people aren't more interested in this stuff! I want to talk about the implications, not all the boring background!