Exactly. People don't understand that many of the yoga stretches are actually making them more flexible in a way that can lead to injury. A person should want their lower back to be strong and rigid (see planks and dead lifts as an exercises) and their upper back to be flexible. Every time I see someone doing yoga and really bending their lower back it makes me cringe.
Someone who knows more about anatomy than anyone I've ever met once said to me: "Half of all yoga poses are great if done correctly, and half of them should never be done by anyone." He mentioned the pigeon pose as a particular instance of a pose that may feel like it's "opening you up" but which, if you're doing it perfectly, is stretching something (hip ligaments) that don't need to - and shouldn't - be stretched.
EDIT: Downvoter, if you know otherwise, please educate me!
Why is there an appendix? Obviously the back is flexible to allow freedom of movement, but that doesn't mean a person should pick things up by rounding their lower back or make it more flexible. Another point is that nature did not make humans in order to have them sit in desks all day. In particular read the t-nation links in the OP.
I spend 15 mins or more of each workout combating the detrimental effects (incorrect pelvic tilt, shoulder impingement and rotation, etc...) of sitting at a desk most of the day.
To be honest, I have a friend who trains athletes (some pros like NFL, NBA) and he helped me out. You can look up many of the exercises using Google, but I would suggest finding a good trainer in your area and spending a couple hours with him/her. A couple hours working out with my friend help me understand what each movement should feel like, which was a big difference between doing it correctly and incorrectly. After that it's pretty easy to do by yourself, and most of the exercises only need a floor you can lay on, a wall you can stand against, and maybe some bands.
