I don't see the point, because I don't see how moving the hips leads to inaccuracy? It's been the method since airplanes were invented after all.
It's gross motor skill versus fine motor skill. I'm not saying that one movement (ankle or the leg/knee/hip) is completely in one category or the other, but the way the muscular and skeletal system work, the smaller and closer to the extremity, the more "fine" a movement can be made. IE if you couldn't move your fingers or hand, moving a paper clip on a table with your arm is far less precise than if you can't move your arm/shoulder/elbow, yet you can move your fingers and wrist. It's much like shooting IMO, some parts of the body are better than others, which is why some types of shooting during stress is easier than others (pistols versus shoulder supported shotgun for example).
I get exactly what WpnX is talking about, and agree for the most part. The distance from the upper leg to the ankle which moves a lot more with a Saitek type of pedals means longer travel and more moving body parts, which = less precise IMO, whereas with the VKB pedals the ankles which have almost no distance from the motion do 90 percent of the motion required to make that motion.
Now, taking Chal's quote, I do somewhat agree that moving from the hip/leg/etc like a typical airplane rudder pedal doesn't necessarily make it imprecise, it can be really precise I'm sure, but just never AS precise as moving from the ankle like with the VKB type of workings. Just my opinion.