Here is a description from Dan on e-budo:
I think the Sumo shikko work is two fold though. The arch for shikko can be used to drive a ground path one side to the other but also in a stand up form to divide and weight drop. One has more significant advantages in a grappling format over the other. But you already know this I think.
Ground work and using the same connections in different planes.
If you are in a top mount ground-and-pound; First try setting up a path from your knees to your shoulders so when he pulls he gets zip- all while your arms are free to whip him or drill. Then if he wins and he does a pull to bring you down to avoid the punches? Use the path from your knee to your arm or hand as he pulls and "ground" through him in his face or neck. It being a new definition to heaviness.
If you have a four corner top mount do the same thing one path to the other criss-crossing. You can also use the ground path to do chokes that most MMA guys can't make work so they throw them away and won't train them. Also to "punish" a guy while working him. With very small movement in a clinch you should be able to use a path to generate power and wind-in at the same time right? If you can- you can do a hell of a lot of damage with your head and hands using your legs and hips. Think about it.
As you have learned it isn't a panacea to all physical dilemmas- but as I have always maintained "It is the best way to train in the world."
If you go to this link http://www.e-budo.com/forum/archive/...p/t-31125.html
there are some fairly extensive conversations about it.