Dcstep,
What is the "best"? You seem to think that there is one objective best and that the manufacturer, particularly of something expensive, should incorporate that in the gear. Perhaps the designer of cost is no object gear used tubes that meet your "best the designers know how to deliver" criteria, it still may be possible for a particular customer to better satisfy his own personal taste or better match the component with his particular system by making alternative choices. That is the reason for tube rolling.
Personally, I would not be spending big bucks on gear if I could not hear the difference and had to "pay experts" to make the choice. This is particularly the case for me because I hardly ever agree with the so called experts (e.g., reviewers).
What is the "best"? You seem to think that there is one objective best and that the manufacturer, particularly of something expensive, should incorporate that in the gear. Perhaps the designer of cost is no object gear used tubes that meet your "best the designers know how to deliver" criteria, it still may be possible for a particular customer to better satisfy his own personal taste or better match the component with his particular system by making alternative choices. That is the reason for tube rolling.
Personally, I would not be spending big bucks on gear if I could not hear the difference and had to "pay experts" to make the choice. This is particularly the case for me because I hardly ever agree with the so called experts (e.g., reviewers).