`It's worth noting somewhere that the term ``sustainable`` or ``sustainability`` is heavily deprecated among Greens and especially Gaians for implying some kind of steady-state output.  In other words, ecological yields vary, and can be maximized but will still vary considerably with weather patterns, insect migration paths, and etc... they can't be made as uniform as outputs of a factory - which almost seems to be the goal of ``sustainability``.  Also, to say something is ``sustainable`` or ``not`` implies that there is some actual test for it.  Which there isn't.  It's all a matter of scenarios and guesses.  The ``Limits to Growth`` type of numerical modelling, largely discredited now, was the actual origin of the ``sustainable`` paradigm.  Today ecologists are far more concerned with homeostasis, keystone species, and homeorhetic process, none of which benefit much from external measures of ``sustainability``.  Complex problem.  Don't pretend to have an answer or a clear altnerative term.`