question: relax structure where upper, middle and lower move somewhat independently or connected? if you are connected, wouldn't moving your hips also moving everything else? in the same vein as your hand connect to your hara, and your hara moves wouldn't your hand moves as well? or am missing the point somewhere which is very likely?
i would add squatting up and down to make sure you don't brace the legs or circling the knees would work too or do both.
Great response from Mark on this already. However, I thought I a saw a post from you somewhere where you mentioned you were in IT. If so, let's take a look at this from a network perspective as well - it just might help some of the technical types to better relate.
To me, I see available energy paths in the body to consist of muscle, bone, ligaments/tendons, and other parts of the fascia. The bone, muscle, and (to some extent) the ligament/tendon paths are mostly linear - the energy comes in and basically follows a straight path through to the destination. However, with fascia, there are multiple paths the energy can go at the same time and still reach the same destination.
If we look at this from a network/telecommunications perspective, consider these linear paths to be essentially dedicated point to point circuits; like Basic Digital Transport (BDT). Now let's consider the fascia to be a meshed network where there are multiple paths to route your data. Of course, in a meshed network you can lock down the routes to simulate point to point paths with a simple routing table, but why limit your options - best to setup a more complex route table that gives you the dynamic flexibility to change things based on the ever changing demand of your data throughput.
Most people have a simple route table for control of their internal energies, and when engaged with an external force, are simply dedicated to dealing with one force at a time that limits thier movements. Now lets say you set up a complicated meshed route table that can handle internal energies in multiple fashions at the same time so you now can handle dealing with ever changing dynamic external forces as well as add some of your own forces to the mix all at the same time. This is what internal aiki training can do for you by establishing new paths for routing energies that you thought were never there because you were locked down in a simple mode.