Alright, I am gonna ask a few questions because [I think] I can relate this thread to another I posted on a little while back...
I think the OP was in regards to energy; I do not believe the vids David posted are energy work, but rather balance shifting.
Balance shifting is fine, but it's not directing energy. We have basic angles that can shift weight, but if I am putting force into my partner, its force work (i.e. physical). This presents a problem for aikido people because, supposedly, we are using our partner's "energy" against them. Eventually, you get to the question, "If I am just pushing my partner over, how is this different than judo?" In the beginning, you gotta learn some basics so we can use vids like what Guy sensei published to help give us some idea of what we are doing. As soon as we advance our education to an uke that is allowed to use gyroscopic stability (i.e. "resist"), we run into a problem because we now need to use more force to shift weight, AND we also have to move faster than our partner because the unbalancing needs to happen before uke regains her balance. We are now officially playing judo with a "push/pull" off-balancing strategy.
Anyone who has practiced for more than a few years should have the joint conditioning and know-how to defend a joint lock. It's a tough reality, but I think important to realize that after 5 or 10 years, most people should only be able to do standard waza on you because you let them. The OP is asking an important question here and detailed a unique feeling.
I am bringing up this point because [I think] it is a good example of aikido people providing instruction that is unclear in producing those traits that O Sensei (and other aiki giants) possessed. We know that our partner should be unbalanced the moment she touches nage - There are any number of quotes in this regard and something that is observable with someone who has aiki. So, adding to our problems from earlier, we also have this issue with an ultimate sensation that my partner should be off-balanced when she touches me.
Nage keeps balance by staying grounded and uke loses balance by being ungrounded.
So how does this happen? At the instant of contact, both things have to happen. We're talking about a vertical pattern here; one part ascending (separating from the ground/ungrounding), one part descending (connecting to the ground). Throw in a horizontal reference (ascending on the right and descending on the left)... It's almost like someone said something like that...
Energy should go everywhere
. When you receive energy, it can't stay trapped inside you; your body, or your limbs, or your joints. So you tease the linear force apart into many directions; some down, some up, some left, some right, etc. so the incoming forces get split and pulled in too many directions to remain a force that can affect you.
So if we go back to nikyo... IF I have aiki... we know that when my nage touches me to start nikyo, I should have her unbalanced. Second, what force she puts into my wrist should be converted into energy work and I should disperse that energy in many directions (depending on who you talk to, there are differences of where). Third, at some point, her force into me gets pulled into a direction of advantage for me and now I have used her energy against her. Start slow - tai chi slow. Let your partner apply nikyo slowly, feeling the binding pressure and then using your muscles to pull the binding out of your wrist and into your forearm, then shoulder, then torso. You are literally learning how to move differently than you normally move, so it will take time. Eventually, your partner will feel a qualitative difference in her success in applying nikyo. You can actually do these exercises with all of the kansetsu waza.
I know, what about doing the waza... same rules... start slow. The instant you touch uke, she should be unbalanced. Not pushed over, not twisted; kuzushi. Take the force she is putting into her wrist to defend you from twisting it and bring it into you - take out the slack of her wrist by pulling it into many directions. In you.
If you don't have aiki, this won't work (because you won't have any actual "energy" to move). It's my belief that the kansetsu waza were intended to be energy puzzles for learning how to use aiki. If you are not there, you need to spend some time cultivating energy and the aiki body.