I've logged in just to comment on this because I think there's some important ideas missing (or perhaps even off base) in this thread.
There's alot of info and research out there now and there's a few key things:
1. There is little to no evidence of "bad" posture causing pain.
2. Pain is not always a sign of damage.
3. "disc degeneration" is a normal part of aging and does not lead to pain or lack of function
The take home message is hurting your back is physiologically similar to hurting your knee or any other part of you. Gentle rehab and then gradual intelligent increases in load/challenge will normally go a long way.
WHAT IS COUNTER-PRODUCTIVE is thinking your back is "mangled" or "wrecked" and stigmatizing certain postures or movements.
So movement and exercises are good but what helps one person may not another (as can already been seen in people's experience in this thread.
Bret Contreras has got on board with this but it's not easy for him and I still see some questionable stuff on his blog. This interview is EXCELLENT:
Here is a one on one interaction which illustrates this very well:
I know this can be challenging, but if what you're doing has helped then keep doing it -Just it will probably serve you better to let go of any ideas of slipped disks and 'bad posture' etc and relax a bit too.