Originally posted by Bronson
What if they are altered to more closely follow the principles of aikido than the original art?
I guess what it comes down to for me is this; do you consider aikido to be a collection of techniqes with some underlying principles, or do you consider it a collection principles, that uses techniques to demonstrate those principles? If you follow the "technique" path then no, none of those other things will ever be aikido techniques. They will always be from that "other" art but sometimes you use them. But if you follow the "principles" path those other things could become part of your aikido if they are done with aiki-principles, aiki-intent, and aiki-mind.
Altering techniques from other arts to follow the principles of Aikido is something that happens. However, not all techniques can be altered to fully correspond to Aikido principles. A kick to the head is still an aggressive move and not part of Aikido, no matter what "justification" is given. Hapkido possibly, but not Aikido.
Blending techniques were known in other arts prior to Aikido. Ueshiba Morihei, however, literally embodied the very principles of harmony and centeredness. He spent most of his life attempting to articulate for others what he understood in his body.
Aikido is a way of unifying principles of onesness, calmness and blending with physical movements which express the same and ultimately lead to "techniques".
Aikido is also a world view.