There is a thing in sports science/ motor learning called blocked learning , that is doing things by repetition to get better. Others thing are random learning, stress training etc.... Different methods of learning have advantages and disadvantageous. Blocked learning develops skills to a point and quite rapidly too, continued blocked practice builds confidence however after a point the skills can actually go backward. Aikido training has many learning elements in its practice - which is great, but its easy to imagine that after 30 years it could all be just 'blocked learning' and so there little learning and even some decline.