Thanks for all the great comments. Marshall gave us a great insight with his own experience with back pain; that he has what would be traditionally considered a strong core, yet he still experiences pain 4 years out despite numerous bouts of p.t.
Porterfield & DeRosa discuss this phenomenon in their excellent book, "Mechanical Low Back Pain"- "Tissue that is significantly injured or degenerated cannot attenuate stresses with the same efficiency as normal, uninjured tissue", and go on to say, "to assume that 3- 45m sessions 3X per week alone will significantly impact long range outcome is unrealistic." (p.226)
This is part of the problem when discussing core. We typically think of core training as strengthening the muscles.
Never forget that ligaments are part of the core system. They don't just connect bone-to-bone. They are rich in Pacinian Corpuscles & Ruffini endings. They are an important part of the core. If we are doing "stiffness" or "bracing" training in the neutral zone, are we stimulating these proprioceptors??? Do most injuries happen in the neutral zone, or rather in the "transformational zone"-where the body is changing directions?
Remember proprioceptors are the spirit of function. When we speak of neuromuscular training, or re-education, this is where it's at. If there is no proprioceptive stimulation, there is no load, therefore no explode. However, as Juan said so well, we need to work at the edge of their envelope of function if they are to improve, and not be injured. We need to safely take the back patient, or healthy athlete into-and out of the transformational zones. On to you guys- by the way, where have all the ladies been???