That's actually a myth. Immobilisations are a relatively small part of the curriculum, and an even smaller part of the overall skills trained in aikido. Furthermore, the techniques themselves are not comparatively safer to an attacker. Actually, competitive arts (e.g. wrestling) are much better at neutralising an opponent without hurting him. I don't really understand what you mean by "repetition" but most aikido training is through solo training and kata. However, there are many approaches and emphases to kata training: Pattern Drills: A Requisite Training Methodology Towards Combative Effectiveness – 古現武道 Mostly agree with this. Just a note on the "thousands of techniques" bit as it is imprecise. Modern aikido has actually very few techniques (about a dozen) performed from about twenty positions. The curriculum is very limited. I guess that you are referring to "Takemusu Aiki" (birth of martial), the idea that application of aikido principles can be expressed through an infinite number of forms, which is quite different.