It's always curious to me that books say keep a shoulder-hip-heel line, but the model's hips in many of these books are slightly behind that line. And chair seat is not the ideal, but what I see in the video looks close to a chair seat. It's occasionally an optical illusion from the boot color blending into the saddle color, but I'm seeing the calf is often nearly perpendicular to the ground and toes ahead of the knee.
