I do not think that "economics" is more delusional here than, say, "Karl Marx" was delusional in Chernobyl. In both cases you deal not with science (even a soft version of it), but with managerial ideologies.
Unlike science that comes with scope conditions and caveats (or it not science but metaphysics), managerial ideology may selectively use bits and pieces of scientific theories to prop its claims, but discard scope conditions and caveats. The purpose of managerial ideology is to provide a rationalization of an already accepted conclusion rather than a causal explanation of facts.
The main difference between the two is the way how they deal with contradicting empirical evidence. Causal explanation (science) limits the scope condition of its claim to exclude such contradicting evidence. If that process goes on, a scientific theory explains less and less (although it retains its validity within it shrinking scope condition) - until it is replaced by a more powerful theory, i.e. one whose scope condition is broader than that of the previous one. Managerial ideology (rationalization) deals with contradicting evidence by selectively adding conceptual devices that neutralize that evidence in some way.
For example, economic theory as science would add such concepts as market failures, bounded rationality or more generally transaction costs to exclude certain situations (e.g. production and distribution of collective goods, or imperfect information) from its scope condition. On the other hand, a managerial ideology would selectively use the efficiency maximization part of economic theory to provide needed conclusions to their paying clients. However, if the efficiency claims fail to materialize (e.g. the skyrocketing cost of health care or power blackouts) it would neutralize the inconvenient facts - usually by claiming that its directives were not implemented as claimed or that someone (government bureaucrats, environmental activists, agents of ___ism) sabotaged their implementation.
The drivel that utilities or communications companies use to prop their drive for deregulation is as much grounded in economic theory of any sort as the drivel that Stalinists used to justify their rise to power was grounded in the theory of Karl Marx. Thus, reproaching economists (or Karl Marx) for the wrongdoings of corporate bosses who hide behind them is barking on a completely wrong tree. Intellectuals only debate the managerial ideologies of corporate bosses differently, the point is, however, to drag these suits from their corporate offices and make them pay for their deeds. Expropriate the expropriators, execute the executives!
Wojtek