Those that hold the pick the "correct" way, how do you palm mute with your fingers tucked in like that? That picture looks very unnatural to me. While I hold the pick like the "correct" picture between the thumb and index finger, my fingers are out and relaxed so I have a lot more control. Makes it easy to palm mute, easy to move from the wrist, promotes a loose grip without tension, and allows me to use my pinky as an anchor. It would seem keeping the fingers tucked in would make it too easy to move the forearm from the elbow.
It's weird to me to even think about something like this. I was a guitar player first and never really thought about it. I just hold the pick how I see others do it and adjust to what feels the best and allows me to play how I want.