Hope these video clips will help:
When you set your camera to full auto, the camera will ONLY focus on nearest point.
For candid portrait, I would recommend to use center AF. I'm quite suprise to see a 5D III user shooting with 61pts auto AF
Thanks the video's certainly did help... sure the center AF is great most of the time but sometimes it needs to be far left or right and the nearest point is okay plus moving it takes to much time or the shot is lost.
Thanks again for taking time to comment.