Align Grid example doesn't change with position parameter set

Grid Align Example

When I add position param:

    Phaser.Actions.GridAlign(group.getChildren(), {
        width: 10,
        height: 10,
        cellWidth: 32,
        cellHeight: 32,
        position:Phaser.Display.Align.CENTER,
        x: 100,
        y: 100
    });

Shouldn’t group be centered in this example?

position is the alignment of each item within its cell (here, 32px × 32px).