There is a chart that is used. When you reach around the coke bottle you are supposed to base your lateral pitch based on where the thumb points in relation to the fingers.
For instance, if it points to the middle of the middle finger, you would consult the chart and see what the lateral pitch should be. If it points between the middle finger and the index finger consult the chart.
Different people's thumbs point to differnt areas of the finger and the chart is set up based on that.