I was fortunate to propose parts of this discussion to Bill Dettmer and Philip Marris, in November 2014 in Paris, and to record as they discussed.
Among the topics: how the name “Theory of Constraints” generates rejection in the business community. The term “constraints management” is preferred by Bill Dettmer and Philip Marris. Philip points out problem is however overstated in the ToC community since approaches such as “Lean” and “Six Sigma” also have labelling issues.
Bill then answers the question “is the Thinking Process part of ToC?” He explains that in his point of view they are both ideas originated by Eliyahu Goldratt but that they can be viewed as separate entities.
Later in the talk, they discuss internal constraints, external constraints and policy constraints, external constraints versus constraints in Sales and Marketing. “Policy Constraints” or policy root causes are described as omnipresent.