But John, saying 'nothing more' is conceding enormous ground. If you are serious about value as the core factor in 'the accumulation process', then that takes you onto all manner of political, economic, social, cultural and environmental terrains, does it not? As I understand the term, a 'heuristic device' is 'shorthand'; but value theory offers a deep-rooted explanation of the laws of motion of capitalism. 'Nothing more.' ?