Every technique just is. Sure you can evaluate on different aspects and find room for improvement. But nothing you do can ever change the technique you just did. When you think "Oh I know this technique" it is only the first sign that you are in trouble. This only kills your Aikido. Beginner's mind...you know nothing attitude....
What do you think is 'spiritual power'? You have explained why you think somethings are not:
Spiritual power is (e.g.) the ability to enjoy yourself, be determined, be aware, reflective and compassionate.
Working on this type of character traits requires change of self...
Another spiritual approach my teacher always tells:
Before executing a technique open your self to the cosmic KI, let it flow in, blend it with the KI of you partner. When the technique fails, you clearly have not opened yourself to KI enough.
and then he smiles sarcasticly...
Let's start with this; I am saying throw the word away, don't use it. The fact that people find it so hard to do itself shows me all I need to see.
O.K. Having said that I'll expand on why. One definition would be to do with the position of Authority, that would be called a position of power. People often say 'if I was in charge I would........ Thus they believe it's a desired thing. Thus they equate it with responsibility. They even equate it with superiority. But they have never questioned it.
Political parties want to get into power etc etc. Do you think that's normal? Do you think that is even wise?
Well her's the thing. If you remove that word and look beyond it you will see there are things preferable or even vitally necessary and far more important to that position of power or Authority and that my friend is ability.
Ability is the word and concept to aim for rather than power. How many political parties or groups or individuals get into a position of power and authority and yet don't have the ability to make things better and thus only make them worse. Yet they cling on to power and it becomes more important to them than their own life and unfortunately usually the lives of others.
So that's a glimpse into that reason.
Now let's go scientific. All physics definitions to do with power are to do with capacity. Well here's the silly thing when it comes to personal desires for power and that is we all have the capacity already. Therefore it's a really stupid goal to have. Thinking the problem in martial arts is that you need more power is thus a fallacy, it's creating a problem that isn't there for having the capacity to do, to handle etc. is already there.
The problem once again is ability and the way to gain ability is study and practice so there is a path to ability.
Now I havn't even mentioned another thing called wisdom here but maybe that's for another day.
So now to your question of spiritual power. We all once again have spiritual potential, spiritual capacity and in fact your spiritual capacity is infinite.
To understand this or rather to transmit that understanding I would use the physical area or subject of energy as an entrance point for such understanding. Thus in Aikido I would get the student to focus on energy. That person attacking you or holding you is to be seen from the viewpoint of energy rather than a physical mass.
A tsuki for example is energy coming at you in a straight line. A shomen is coming at you in a straight line, it's cutting through straight through your centre line. On the other hand a yokomen or a right hook or a roundhouse kick etc is energy coming at you in a circular fashion, on a circular line.
Then there is the focus of energy towards and through you which can be represented by the triangle. So you see here I am relating energy motions and the looking at the from the view of geometry.
Why? Because it will lead a person to understand better what they are actually dealing with and meant to be harmonizing with. Secondly it is leading a person towards principles of energy and those principles are the vital factor necessary to understanding.
Now if you were to enter the field of structural engineering you will find they deal especially with the principles of energy. The preferred pathways of energy.
Therein lies the key to understanding. Energy follows certain paths of which there are not many actually so when you try to block someone or insist on energy going a certain way you would be defeating yourself or at least making it a thousand times harder by ignoring or attempting to ignore these principles of energy motion.
Now note the word principles. Truths. The basic laws that energy follows in motion.
Learn these well, become able to recognize them and know them,and see how the apply to all motions and techniques and then you will know a great deal about Aikido.
The funny thing is that spiritual energy or Ki follows the self same principles. So if you were to study that and practice that and get to a level of ableness, ability, where you are in tune with and operating from those principles comfortably the that would be spiritual power. But by then it would be just normal to you and nothing really to you and thus power would be a word used by others.
So there you are. I hope you're still awake. Ha, ha.