For "who won" you don't compare to the field, no
But for domination of a market product you absolutely compare to the field. Nintendo utterly dwarfed the other guys. PS2 vs GCN/X-Box is not really comparable.
Oh, so selling 6 times as much as your closest competitor is only "dominating" if you only have one relevant competitor. If they're two, it's "selling a bit more." Gotcha.
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Blitzball fan? Try Captain Tsubasa II (in English) for NES!
Game reviews/articles by me: http://betweenlifeandgames.com