This method is a tool to help you draw the human form. It is by no means the best way or even a fast way. Instead, this method is aimed at thinking and setting up the human form in a threedimensional space. Classical animation (most notably Disney) uses a similar way of working out their characters. In these kind of animations a good understanding of the character in a threedimensional space is important to achieve a convincing motion in time.
Using this method will help you form your thoughts on the human body posing on paper rather than in your mind. It will also help you avoid that frustrating 'running out of paper phenomenon'.