I completely agree with Chuck Clark. To train only to reproduce what you have been taught is ultimately wasteful. If a species does not evolve it dies out, the same could be true of our martial art.
Anyway, each time it is passed on and reproduced it will be dilluted like chinese whispers, so trying to faithfully reproduce it is futile. The art must evolve. Your Aikido must be YOUR Aikido.
I cannot do Yoshinkan just like Kancho Shioda as I am taller, heavier, and obviously a different shape. So I do MY Yoshinkan Aikido, within the principles.
We must try to be faithful to our teacher's Aikido at first, as we are learning the under pinning basics, but later we have tofind our way.
I disagree with the analogy with music though, Chuck. Every singer has their own voice, just as every pianist has different weight and timimg, every wind player their own vibrato, etc. They play within the notes their way, so I think Music sits very well as an analogy for finding your Aikido "voice".