Not an economist, but my job role involves lots of economic theory and I'm a few classes into an econ masters. As far as economic reasoning goes, there are som

Not an economist, but my job role involves lots of economic theory and I'm a few classes into an econ masters. As far as economic reasoning goes, there are some studies you can do (like optimal auction clearing) where you can hold the inputs equal and then adjust some aspects of the optimization (the objective, constraints, or decision variables) and get a very accurate picture of how market changes would impact the results. I think that is probably an exception rather than the normal case though. In general, my thoughts during my studies has been that the economic theories of supply & demand, incentives, elasticity, theory of the firm, game theory, government intervention...etc all has more use as a generic framework of thinking (ex: if we put in a price cap, here are the expected impacts), rather than an equation I can use to get an exact answer (basically exactly what you're saying above). Doing some kind of analysis on things as complex as the US economy must have massive inaccuracies involved as there are too many factors and even behavioral economics doesn't have all the answers for why people don't always act rationally.