It sounds like to me the SOB carry is actually almost right over the spine? I have tried placing my weapon there and I have to admit it is comfortable but it scares me. I carry behind my hip and keep my weapon off my spine. (yup I am gonna say it) In my carry class the instructor spoke about SOB carry and brought up the point of sweeping yourself and also that if you slip or fall on your back what kinda damage are you gonna do to your spine? That is why I carry behind my hip I figured I can live with a broken/repaired hip easier then a broken/repaired spine. I will note that I carried with a GA license for close a year before getting my TN one so the instructor did not effect or change my mind on how I carry. (I live in GA but am a resident of TN and that is why I have both)
"The purpose of war is not to die for your country. The purpose of war is to ensure that the other guy dies for his country." - General Patton