If an innovation in the means by which a good which enters into the
workers' consumption is more widely used, due to its increasing cheapness,
and thus helps to make a wage good generally cheaper and so reduce the
necessary social time of all workers, then that innovation raises the rate
of exploitation for capital as a whole--the extra surplus value does not
accrue directly to the innovator and will not obtain at all if the
innovation is in, say, the polishing and cutting of diamonds.
It is my sense, though I still don't have the skills to make the argument
systematically, that innovations only bring the progressive capitalist
extra profits through value redistribution (I remain a student here of
Carchedi and Kliman), while, if meeting the conditions noted above, help to
raise the general rate of surplus value, the determination of which can
only be grasped at the level of capital in general.
I will have to look again at Geoffrey Kay's The Economic Theory of the
Working Class again (New York: St Martin's Press, 1979). If I remember
correctly, he has a scintillating discussion of how through competition,
capitals realize their cooperative exploitation of the working class.
Rakesh