The status of Marx's reproduction schemes: conventional or dialectical logic?

In Part Three of the second volume of Capital (Engels’s edition 1885) Marx presents the macroeconomic circulation of capital in terms of what he calls ‘reproduction schemes’. The main part of the paper outlines Marx’s fascinating design of the schemes. Next, this design is examined from the perspective of his method: is it akin to a modelling approach as we find it in modern orthodox economics, or does it rather fit into a systematic-dialectics methodology?
More so than any other part of Marx's work, his theory of reproduction influenced orthodox economics: it laid important foundations for its later macroeconomics and theory of the business cycle. Why particularly this text? In answering this question the paper examines the systematic character of the exposition of Marx's reproduction theory, focusing on its procedure in laying out assumptions. It is concluded that, while the text may not be incompatible with a systematic-dialectical methodology, it is defective in that respect; rather the textual evidence favours the view that Marx, in this part, takes a particular modelling approach.