Just a small point, MtheGM; there is no Firm Law of Unforeseen Consequences; if it was a law, unforeseen consequences would become expected consequences. I think what you are referring to is the discipline of non-linear complex adaptive systems (sometimes erroneously called 'chaos theory), one of my research interests. If such a 'firm law' existed, then it could be used as a means of preventing change in any field, by the expedient of saying 'we can't change because there may be unexpected consequences'. By your logic, we would still have slavery, public executions, bear-baiting, no votes for women...need I go on? All of these were 'arguably ideologically questionable but pragmatically functioning present arrangements' in their time.