I was watching the Pose Running DVD the other day and reviewing the drills. I soon realized that many, if not most of the drills, are similar to jump rope movements. Many of the drill variations - hopping on one foot, hopping forward and back, side to side - are reminiscent of the drills you see kids do when jumping rope.
I found a couple of other things related to jumping or elastic recoil in regards to running. Here's a section from "The Lore of Running" by Tim Noakes (citing research on turkeys):
"The muscle contraction was just enough to keep the tendon stretched when the foot was on the ground, thereby storing energy for the next stride. As a result, the muscle shortened relatively little and used only a small amount of energy when the turkeys ran on flat surfaces. Most of the work of running was done passively in the elasticity of the muscle and tendon."
A different piece of research looked at the contribution of plyometric leap distance with regards to 10k performance. The study found that 74% of the variation in 10k time was due to differences in plyometric leap distance. This is a remarkably high portion to be explained by just one factor.
I think that good runners utilize elastic recoil and end up bouncing along in an energy-efficient manner. Inefficient runners try to muscle their way to faster speeds, by pushing off with muscle effort or pulling the body forward. It's a given that people will have different levels of elastic recoil in their legs, due to differences in achilles tendon length and the arch of the foot. Learning to properly use elastic recoil will likely lead to faster times and fewer injuries.