Re: final lock doesn't work
Well the thing is that a lot of aikidoka all over the world think that they have been on the receiving side of some totally 100% immobilizing pin. That has to be included in any reflection involving what may or may not be on the other side of ignorance. This is because delusion - especially self-delusion - is just as warping as ignorance when it comes to issues of truth and accuracy.
As far as that goes, the key word here is "think" - and what goes unnoticed in all that "thinking," and then of course also in the hoping of being able to one day do what they thought they "felt", is a whole lot of culture that has nothing to do with the pure and simple task of pinning someone down that does not want to be pinned down.
When you see someone being pinned from one corner of their body, I would propose, you are viewing, at best, an unconscious application of a training culture (i.e. a kind of ignorance in and of itself). Let's remember, it is a basic principle of Aikido waza that one should be able to move at all times: If someone has control of one of your corners, move your other corners, and then that person won't have control of that one corner any longer, etc.
What one sees when Aikido pins "fail" against escape attempts is nothing more than this basic principle (i.e. the person is moving their free corners - the other centers they have at their disposal - thus nullifying the control the person had on the first corner). If a person doesn't have movement of these other corners, then its primarily for one of three reasons: 1) One of Aikido's most basic principles is flawed (which I do not think it is); the person is subconsciously allowing their other corners to be controlled via the assumptions contained within a training culture (e.g. "When I pin your arm in ikkyo, try to move your arm."); or the person feeling totally immobilized doesn't understand this basic principle of Aikido waza and simply does not know how to move his/her other centers to free the one center once being controlled.
In my opinion, one has to equally consider all of this, weighing it carefully, fully, against any position that posits "if one really knew what he was doing, he would know how to 100% immobilize a human body in the prone position by having contact with the elbow point of articulation alone (for example)." Why? Because while it is easy to be wrong about what one knows, and though it is difficult to attain high levels of training, the easiest of all things to do is to say, "Well, you can't do it because you don't know, and you don't know because you can't do it." - having that justify anything and everything that does not work as expected.
For me, I have to feel it, then I have to understand it, then I have to do it, before I go on thinking that other folks' position is supported solely by ignorance (i.e. a lack of wisdom and insight). If I hear it from someone else, before it carries any weight (which is that solely of consideration), I have to know that the person in question has legitimate martial skills (i.e. skills at countering and neutralizing attacks - launching them as well). That said, I think there are a lot of aikidoka out there that could quite easily be pinned by solely having one corner of their body controlled (as in Ikkyo). It's just that this is probably more related to an ignorance regarding martial skills than it is to any wisdom regarding pinning. In that sense then, we are at an impasse regarding where ignorance lies and/or where wisdom lies.
All the more reason to keep thinking and training with and upon these things.