As to Kalecki's role in the use of the term macrodynamics, Barkley is  
right in his latest post: Kaleci almost surely picked it up from  
Frisch. In fact, in a footnote to his 1935 Econometrica paper,  
Kalecki points out that

"The term "macrodynamic" was first applied by Professor Frisch in his  
work
"Propagation problems and impulse problems in dynamics" (Economic  
Essays in
Honour of Gustav Cassel, London, 1933), to determine processes  
connected with
the functioning of the economic system as a whole, disregarding the  
details of
disproportionate development of special parts of that system" (p. 327).

As to macrodynamics and macroeconomics, there is of course a big  
difference: the first applies to dynamic systems (that is, in  
Frisch's own terminology, systems where the state at one instant -- 
wich includes values of the variable at different times-- determins  
the successive states), while macroeconomics may well include static  
systems --e.g., Keynes's.

If I am allowed to say so, my paper cited by Barkley, "Formal  
modeling vs. insight in Kalecki's theory of business cycles", is now  
published in Research in the History of Economic Thought and  
Methodology, vol. 24-A, 2006, pp. 1-48.

Daniele Besomi