I'm not sure what, exactly, you are asking here.
But, to me, it's like asking:
How is a spoon a spoon?
How is a spoon not a spoon?
And, I guess I'd answer it by saying that a spoon is only a spoon if you use it as such and that the word "spoon" is not the thing "spoon."
Aikido is Aikido as long as it IS Aikido. The same could be said for anything and everything in the world. But "Aikido" is not Aikido. Aikido (and everything else, ever) just IS. There is no "Aikido." There just...is.
Catch my drift?
Well, it's like saying, okay, you have silverware. What makes a spoon a spoon to you and what makes it not a spoon?
I see answers like:
I can eat with the spoon.
The spoon is a spoon.
The spoon picks up food.
The spoon fits in my hand.
The spoon is a utensil.
While all well and good and do define a spoon, they also define all other silverware. And they aren't really answers to the second question.
A spoon catches food in the curvature better than a fork.
A spoon will ladle while a fork will sift.
A spoon can be used to cut but depending on the user, it might not cut as well as a knife.
So, if someone says that aikido is aikido to them because it is a path of least resistance, then that is exactly what judo does. So, how is that definition not judo to them? And, what makes it NOT aikido? What defining limits are there that do not spill over to judo in path of least resistance. If you look at Mifune, he could have done aikido easily. Yet, all can tell that he isn't doing aikido. He's doing judo. But, most answers that I saw here apply equally well to what Mifune does as they do to aikido. How then, does that replied answer define what makes Aikido aikido to them?
Am I making any sense at all?