Charles I simply meant they get it right for their products as designed not that they do it any better or worse than others who do it differently for different reasons. Practically their tube amp market share probably does help confirm the relative effectiveness of their approach for many using many different speaker designs.
I would love to own a VAC but would probably only do it if I were willing to build my system around it, mainly the speakers. Atmasphere (OTL) is another example of a higher output impedance tube amp that dictates certain speakers more for best results. SET tube amps are of course another.
ARC tube amps would seem to fit better for more that build around certain speakers that may be a harder load to drive but still prefer a tube amp.
Different strokes......