Unsound, you used the phrase
numerous requests
Your request for links which I provided does not constitute the above and my response also satisfied your lone request.
So your statement above is clearly misleading.
With regards to Norman Crowhurst, he does imply that negative feedback is beneficial. I pointed to him because he supports my claim about odd orders being distorted in a small degree by the presence of negative feedback. IOW he does not make a value judgment- that is made elsewhere, for example by Nelson Pass.
However in Crowhurst's text if one is familiar with Chaos Theory
http://en.wikipedia.org/wiki/Chaos_theory we see that Crowhurst shows the formula for feedback; compared with that of a classic chaotic system that the two are nearly identical. He also mapped the Strange Attractor that is characteristic of the resulting Chaotic system that an amplifier is when using feedback. These things are not coincidental; the presence of bifurcation (distortion) is predicted by Chaos Theory and Crowhurst, despite Crowhurst's writings preceding the formation of the branch of science we call Chaos Theory.
Now the fact that Chaos Theory predicts negative feedback to be a destabilizing factor in amplifier design is something that should not be ignored (BTW, many designers will mistakenly claim that negative feedback is a stabilizing factor). However no value judgment is made, simply the expression of what is.
It is other studies including the rather simple and repeatable test (to which I have already referred) that make the value judgment. That judgment is not entirely mine, BTW, but a fairly large consensus in the audio community which agrees that odd orders are unpleasant to the human ear (and is the reason that over 50 years after the introduction of transistors, tubes have failed to become a footnote in audio history). All I have done is outline what is.