I share Perry Anderson's sense that Sweezy's Theory of Capitalist Development had important consequences. But there a few things to say here. First, Mario Cogoy made the same argument a few years earlier in an exchange Sweezy broke off--see International Journal of Political Economy, vol 17, no 3 for translations, though John Bellamy Foster would later come to Sweezy's defense. Second, while Sweezy unintentionally opened the door to the abandonment of the labor theory of value by endorsing Bortkiewicz's equilibrium simple reproduction set of simultaneous equations, it was actually Perry's press Verso that did the final burial of the labor theory of value and the falling rate of profit as it published Steedman's Marx After Sraffa and Marco Lippi's book on value and naturalism. NLR's crisis theory as expressed by Brenner does not depend on Marx or the labor theory of value or the falling rate of profit, and can be shown to imply the same possibility of stabilization of capitalism as Sweezy is said to have, though for Brenner the instrument would not be Keynesian planning but the regulation of trade and international competition--the putative causes of the great downturn. I made this argument upon immediate publication of Brenner's NLR issue on this list. Third, the importance of Sweezy's text should not be exaggerated as in crucial places he is only developing the positions of the right wing Austro Marxists--Hilferding and Otto Bauer who did not survive the Nazis. Sweezy did not create what Perry is calling revisionism. If it closed the debate with the other purer Marxisms, it is only because the representatives of those schools did not survive Nazism and Stalinism.
While every word of Gramsci and Lukacs have been studied, not enough attention has been paid to the actual writings of Austro Marxism. Too scientific for the cultural and philosophical Marxists and too bourgeois for Trotskyists. So their work has not received the critical attention which it deserves, including the splits within it.
Rakesh