For zooms, maybe but when sigma can equal or beat them out with better built primes for less money I have to wonder.
Well, I understand what you are saying here, but please note that I am not saying that Nikon is superior, I am saying that they think they are.
To give just a couple of examples, what seems pretty clear is that Nikon didn't try to release an overly sharp lens with the 58mm f1.4, they went for a "look" lens with pretty unique bokeh characteristics and have managed to generate a pretty impressive follow up. Just look at the 58mm thread at Fredmiranda.
So they seem to have achieved what they wanted and it only confirms their own view about their excellence, even if it may not be shared by a majority of pixel peeping/DxO driven group of people.
Regarding the 35mm f1.4, I would tend to agree with them, the Nikon is IMHO superior in terms of bokeh/look while being close technically when compared to the Sigma 35mm f1.4 that I own. Few people care in the West, but in Japan - the only country that really seems to matter to Nikon from a product spec standpoint - those lenses are not seen as being in the same class.
And they are clearly not trying to compete on price with those lenses, that is the role of their f1.8 range.
Anyway, I am digressing here.
Cheers,
Bernard
