Adding another spring ...even with the same amount of trem angle on the bridge from the body will make the trem block more stable and faster because of the added spring tension. It will fall "in place" faster and more consistant thus keeping things in better tune when floating. For me having 4 springs helps if I put them on the outer edges of the claw. 2 springs at each edge. 3 springs in the V shape (one in the middle and the 2 outer springs angled toward the middle spring on the claw) seems to be less stable than the 2 springs per outer edge way. At least it is for me.