What do mean with "technique in itself"?
So in my understanding it is just and "only" technique that works. But I think we may call different "things" technique?
It is difficult to explain but what I am trying to get across is that a person's aikido only works if it applies to ALL body morphologies he encounters: small, tall, stout, skinny, strong, limpy, hunched, straight, muscled, etc. But the thing is we don't have the opportunity to train with every kind of body shape, size and strength such that we can only wonder how good (or bad) our aikido is.
The more years or decades you train in the art, the higher the probability you can make the techniques work on a large number of people but that does not mean you understand the art. There must be more fundamental than "technique" that needs to be understood if ever one is to progress significantly.