One of the benefits of LensAlgin is that you get to "tune" the AF front/back relationship to your liking. Many people have a mis-conception about the front/back relationship of DOF. While at Infinity and long distances the classical thinking is true...33% in front and 67% in back. But rapidly as the distance comes off of infinity, the front/back relationship speeds toward 50%/50%.
With the camera's AF Adjustment and LensAlign we can choose to adjust our lens to mimic the theoretical ratios, OR we can center the focus point in the center of the DOF which gives the most leeway for the sporadic AF "errors" that can move the focus point around.
We also have the creative license to push the focus point toward the front of the DOF to give more focus percentage behind the actual focus point, which some photographers prefer. For example if shooting head/shoulder portraits in close you may want to set a front focus bias (80/20) so that when focusing on the eye of your subject, the back of the eye and all other facial features (nose, etc) are within the DOF. Be careful that you always check how your AF Adjustment settings affect other distances.