Shouting about it doesnt help your weak point. Julian was one of my mentors. When I studied with him he shared that, in fact, he did hear differences in the sound of power amplifiers. However, it was his opinion that the differences were so minimal as to be of no consequence.
So actually, it was simply a value judgement on his part, as it is for all of us, what has value and what does not. See, I got through a whole post without putting a slew of words in caps, LOL.