And it is are also a great place to break something. If you fall, unless you tripped over something, odds are you are going back. At the small of your back, all the pressure will be on your spine, unlike a pack where you will have pressure on your shoulders and hips.

Also, I hate to say this, but SOB carry isn't very subtle. It looks subtle to most people. Most people also have to ask "does my butt look big in this?" It shows horribly in my experience.