All you need to know about appendix carrying
Conceal carry can vary depending on the gun being carried and location. This article will delve more specifically on appendix carry.
ADVANTAGES OF APPENDIX CARRY
Appendix carry has great advantages, other than being the current fad. One advantage is the ease of draw. The draw is faster than a side carry specifically while concealed with a shirt over it.
In appendix the non-shooting hand lifts the clothing up out of the way, and the shooting hand can draw the gun freely. Keep in mind most self defense shootings happen within 0-7 yards according to the FBI.
Appendix carry allows for quick access to the gun and as you draw you can shoot the gun with one hand as the non-shooting hand is handling the clothing.
Try side carrying and drawing from concealed with some article of clothing over it. Removing the clothing can delay the draw or get the gun tangled in the clothing. Appendix also helps keep the gun secure in a scuffle. Since its in front, the chances of it getting removed are far lower than side carry and low of the back carry.

THE BOTTOM LINE
You can become proficient enough in any form of conceal carrying but with no training you might as well not carry. Train as much as you can since you are depending on a firearm to save your life. Do not be fooled by your ego, learn and practice.