"James, for someone who arranged such a marvellous early 1990s retranslation and (Pluto Press) publication of Grossmann, it seems like amnesia regarding fictitious capital has set in. How come?"
How does this follow from my pointing out that Marx's category primitive accumulation described the origins of capitalism and was not typical of accumulation today? If I did not mention fictitious capital, it is because we were discussing primitive accumulation, which, to state the obvious, is not the same thing as primitive accumulation.
In general, I find, Patrick, that you read more into Grossmann than is there. If I can characterise it this way, you find that Grossmann discusses the more developed forms that capital takes (share capital, fictitious capital and so on), and you think that sets the precedent to re-focus the enquiry from onto these phenomenal forms of capital accumulation. But it seems to me that you misunderstand Grossmann's method. Grossmann, who is meticulous on the methodological point that one ought not to confuse different levels of analysis, discusses fictitious capital under the heading of the 'modifying counter-tendencies' to the law of breakdown. That is, they are derivative, secondary effects, that react back upon the underlying trajectory of capital accumulation, but cannot reverse it. Grossmann saw fictitious capital as unessential, a phenomenal form that capital took. Interesting as a manifestation of the inner contradiction, but not so vital as to bear the weight of an explanans explanandum that you make it. None of this, by the way, has any bearing on the wholly unrelated category of primitive accumulation.
And of course you are right to say that the real course of events will not be decided by books. But in that we are discussing Marx's concept of primitive accumulation, it seems to the point to say that it is being misapplied, no more meaning 'fictitious capital' than it does 'finance' or 'cuckoo clocks' for that matter. And one might indeed say that it does not matter if you use these terms in a different way from Marx's meaning, but then why call it "primitive accumulation", a coinage quite patently meant to explicate the common political economy term "original accumulation"?
Elsewhere you invoke Rosa Luxemburg's name in support of the theory of primitive accumulation. And that is right, in that she argued that insofar as Capital creates values greater than it consumes then it would need to conquer ever greater markets in which to realise this surplus product. But Luxemburg was wrong, as Grossmann indicates on pp 164-5 of the Law of Accumulation... saying that she imagined that she had found a gap in Marx's system and 'then constructs a theory to fill this so-called gap' a procedure, he says that 'shatter the underlying unity of the [that's Marx's theoretical] system and creates a hundred new problems'. I suspect that Grossmann would have endorsed Paul Mattick's view that Luxemburg's theory of 'noncapitalist markets' 'had nothing to do with Marx's theory of accumulation', and that furthermore 'Imperialism ... can be treated in connection with accumulation, without reference to the need for noncapitalist markets for the realisation of surplus value' (Economic Crisis and Crisis Theory, 1981, p 90)