The only thing I can say to that is that when we sit in lotus, right foot first, then the left heel is higher on the body, pressing in on the organs at a higher location than the right heel. The body is assymetrical inside just as the heels are in placement. I haven't heard any explanation further than this. I wish I had more technical answers to a lot of yoga questions, but I finally let that do, knowing that there's always going to be unknowns. This lotus postition just comes natural for me now, and I put faith in the system! Hope that helps a little.....