If you're reading this for this first time, check the topic on "resonance" first.
When a body is moving energy through it, that moving energy needs to drain out of the body. This is vitally important. This is the same concept as a sink with running water. The water must constantly drain, or it gets back up. That's exactly what happens with your body when we don't properly drain the energy AS it runs through.
Is this literal? I usually do not ever feel in a state of "overcharge" - no do I usually train to retain [any] energy that enters my body, or even allow it to enter my body.
A few misconceptions. We do not get power from the ground. The earth has no power. It's receptive. All power in the earth comes from the sun. See the "Trees grow from the air, not the ground video" in this forum. Even power that's in the earth, came/comes from the sun.
I am not sure about this. Gravity pulls us into the Earth, but Earth spinning pulls us away from the Earth; the balance of these forces keeps us both from being flung into space or squished. Sounds to me like we can get power from both the Earth or the Heavens...
When you jump a car battery, all the power comes from the positive lead. The ground lead can be attached anywhere on the car that will allow the charge to drain. Often the frame of the car is even better than the negative contact on the battery.
When you jump a car, you deliberately create a neutral circuit by clamping a ground; this prevents the negative connection that would complete the electrical circuit and cause a spark - this is an issue of safety, not electricity. Electrical circuits needs a positive line and a return [negative] line to complete the circuit, the "ground" is a neutral line - often not even insulated because it does not carry a charge. Again, sounds to me more like a balance of forces.
The best way to decouple a body, is to provide a structure at the bottom of the body that best allows the energy to drain the most efficiently.
Flat feet: Have you ever had neighbors above you that had speakers directly on the floor - and it felt like the music - especially the low end - was just booming all over the place. What they'd basically done is to turn their entire floor - and the walls - and to some degree the entire building into a big speaker. Feet placed flatly on the ground - or floor - act in the same way as your neighbors speakers on the floor. And those vibrations and built up resonances not only go back into the speaker body (your body) but they also "couple" with the floor and walls. Making all that "one body." A big mess.
You've also heard of a "heat sink" a similar process. It drains the heat away by quickly draining the heat (energy) to a larger surface area where it can dissipate. And that's why they call a kitchen sink a "sink." Sink does not mean to "lower your body structure vertically." It means to discharge the energy in your body through your legs - to your feet and toes - and out in the the ground.
The energy in your body, in order to drain and dissipate fast enough so that you don't turn into a big overcharged battery - is by "decoupling" your body with the ground/floor. The way to do that is by forming a smaller coupled surface at the lowest part of the structure- ideally in an upside down cone shape - that allows the energy to spiral downward - out of the body - and into the ground/floor.
You have something that's shaped just like upside-down cones on your feet. The toes.
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I got a automated message to post something... Here goes.
I appreciate that you are making an effort to explain internal training as it relates to aiki, or more importantly, aikido. But, I am a little confused by some of the comments you initially make, as well as some follow-up comments.
To start, I bolded under your original post some comments.
I am unfamiliar with the concept that you want to allow energy into your body, even if to dissipate it. Are you saying specifically that you are creating a body structure that is designed to receive and dissipate energy? How is this different then creating a structure that never lets in energy?
Also, my understanding of decoupling is a separation of objects. For me, to decouple from the ground is to separate yourself from the ground...
Anyway, hope my comments help.