An article "P-Chain Thang" describes Tracy Fober's take on the posterior chain.
…."The kinetic chain includes the foot, ankle and knee. Without the musculature about the foot, ankle and knee, the hip is worthless. Strength, power and agility are about coordination and force production / attenuation via interaction with the ground. All ground-based movement is the result of a complex interaction of many systems, not just the hip. Instead of focusing on the hip down, I'd encourage you to think about force production from the ground up. Instead of focusing on strength, focus on skill, stiffness, reflexes, coordination and effective use of ground-reaction forces. Muscles are nothing without the nervous system and gravity.
By all means, squat til' ya drop. Live in The Big House. But keep the big picture in mind."…
We hope that what our readers get from today's article is that proper biomechanics is key and let's not forget that orthopedically sound range of motion is king! ~ Atomic CF Coaching Staff