Surely the basic objection to one sector models is that
they do not deal with the capitalist mode of production, since
that has to be a form of commodity production which presupposes
a multiplicity of different physical products with money prices.
At most they might be of some relevance to modeling things like
cell growth in the presence of a single nutrient.
Having one sector is quite different from forming monetary aggregates
for the whole economy, since the latter makes no mention of physical
quantities.
Paul Cockshott
wpc@cs.strath.ac.uk
http://www.cs.strath.ac.uk/CS/Biog/wpc/index.html