1. As a body of knowledge passed from person to person, Aikido isn't "self-correcting".
2. Aikido is martially effective.
I believe that 2 supplies the feedback for self-correction, and that refutes 1.
If not, then you are making a third assertion:
3. Aikido must have a certain form or else it is not "true" Aikido. Therefore, even if what a practioner does is martially effective, and was attained using Aikido training methods, then it is not at all Aikido.
I don't see much use in that idea.