Differently, check out Vishaan Chakrabarti's A Country of Cities, which disagrees with Krier (and thus agrees with Wright) on the skyscraper: http://www.amazon.com/Country-Cities-Manifesto-Urban-America... It suffers, IIRC, from not enough citations but is otherwise pretty strong on its argument.
I tend to lean towards agreeing with Chakrabarti and Wright more on the vertical space issue, largely because Krier never quite managed to form a coherent argument against density except that it was being done badly. Krier, on the other hand, highlights the idea of the poly-centric city which is at least a reality in Seattle (where I live).
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