I must be the simpleton of the bunch here... I train in Aikido because I enjoy it and I enjoy the fundamental contradictions contained therein. And I like to train with people who can stop me. So I try to learn what it is they're doing to stop this > 225 pound Norwegian who polishes swords all day and can usually crush folk at will... I have teachers in our org who can do that. I have seen it in guys like Dan, Mike, Toby, students of Ark and others. So I search them out.
To me the answer lies with me on the mat when I'm on my back wondering how the hell I ended up there. No more questions after that. Power? Aiki? IP? Um, sure, whatever. Haven't heard a really good explanation yet that satisfies my western sensibilities. Till then... I keep searching it out, whatever it is.
And some can transmit it a heck of a lot better than others. Shrug.
So how many angels can sit on the head of a pin?