I myself hope that no one ever clips the wing/s of their bird as the one I was gifted. Please do not reproduce that!
But I have already told you we will have to agree to disagree on this!
To others I do not experiment on my birds, I try to keep my birds happy. I will forever disagree with the way clipping (both wings) is described in this thread (or over clipping one), and I will never clip more than one wing more than the light tips of the feathers. That is all that is ever need to stop fight. And if you take to much, not only can the bird be damaged, but may not be able to get away from a predator. Find the problem and fix that instead.