Im actually very good at fixing backs. I look at them as a back pain sufferer, a fitness instructor, a massage therapist, a sports person , a hypnotist and an avid student of the many techniques and idea  published  both  in hard copies and on the internet.
However, when ever I fall in love with a theorist, like other practitioners, I go wrong. Of course all practitioners will claim that they assess what they see. I doubt this. We tend to view the world through lenses, and sometimes assume that identifying a problem, precludes the existence of other problems.Otherwise what the point of having a belief. Which Fan of Stuart McGill doesn’t go looking for a flexion based problem?
So, anyway, I was working with a client,and we began the process of fixing by looking at his life style , what he was doing, etc, and basically concluded that his issue was a flexion issue: certainly be benefitted from evaluating his squat form,  developing his hip and shoulder flexibility , grinding out some scare tissue , and building up his core strength and endurance, and realising how much he used his back.
Nevertheless as we came to the 3rd session we realised there was another factor at play. Strangely, like me,  he accepted that he stooped, but we traced his actual injury down to an over extension fault in the squat: he had attempted a squat with his torso bolt up right,  and obtained the extra flexibility the position demanded by over extending, and collapsing at his lumbar curve at the bottom:
so a couple of extra observation, based on his feed back and mine.
1) if you have back issues, the chances are that your perception of your back position if wrong: you simply dont know what the feedback means
2) Is it  possible to tweak your back by over extending and  flexing at the bottom. Yep, you can have both.
So, I started photographing lumbar curves in a toes touching position and noted that quite a lot of people have immobile lumbar areas in flexion: they  flatten, they don”t collapse ( see the montage).  is there a relation hip between the depth and quality of an overhead squat and the position of the lumbar curve in the toe touching position? If you don’t flex your lumbar spin, isn’t coaching you to make a big chest running the risk of an over extension injury. Do we now have a potential easy to do screen.
Im off to photograph lots of overhead squats and toe touches to see if there is some sort of correlation