There are real-world scenarios in which a concealed carrier might have to present the gun, or ready it in hand, in a stealthy. This is done with what is called the surreptitious draw. Being able to draw your gun without attracting attention from an adversary, or multiple adversaries, is an important skill to work on.
As an example of where you may encounter such a need, consider being seated at a table when a violent criminal enters to rob the establishment. Or, consider standing in a grocery store where you have sight of the adversary, but your waistline is hidden from him by an isle or shelf. In either case, a surreptitious draw can facilitate getting the gun in hand without the adversary knowing. If you get the sense that the criminal actor is about to start killing people, getting the gun in hand will make your response that much faster.
A surreptitious draw involves unholstering the gun while minimizing your motion, particularly in the elbows and shoulders, as these are the areas that telegraph the draw. In our given scenario, your hands and waistline would be out of sight, but your elbows and shoulders would be visible, thus minimizing the movement in those areas becomes necessary.
Carrying in the appendix position offers a significant advantage in this technique for most applications. If you carry strong side hip, the surreptitious draw will rely on blading your body so that your strong side is not visible to the adversary. If in a seated position, however, the appendix position facilitates this technique much more effectively than strong side.
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