Personally, I feel that it has to do with if you have a finicky hand or not. Some people do not. I do. I know some things for a fact with my hand. When my hand lays on the ball with just my thumb in, my fingers centerline is not the same as the actual centerline.
Now, if I twist my hand and make it line up, my thumb doesn't lay in the hole correctly. In the direction that it is pushing, it could make me come around the ball early, or pop my elbow out. So, I choose to go the ergonomic route, and do what my body tells me it should do.
What this ends up doing is it allows my fingers to lay in the hole at the angle in which my hand is designed, not what some other person thinks is right. Now, I know the argument of "Yeah yeah, if you just do it off of the regular lines, and just "copy" the pitches off of the ball, it will fit the exact same.", and it's depends on how feel orientated you are. Personally, you will never gain the same feel, even if you "copy the pitches", because there are more forces at work in the hand than just "Do the thumb and fingers fit?"
If your thumb pitch was wrong, you would know it, right? What about the angle of your oval in your thumb? Would you feel that as well, or would you just deal with it, knowing that something could be changed in which would make you release the ball cleaner without effort?
This is a "You say tomato, I say tomahto" conversation, but it works for people that can feel it. Those of you that can't feel it, God bless ya.
The sky is falling
The end is near
The final warning
The sun disappears.