But there are economic reasons too. The Americans, who have the perverse habit of hooking as many cars as possible to their locomotives, force them to work at long cut-offs to get as high an α coefficient as possible so as to have a good use of the (expensive) adhesion weight. This of course leads to a high specific steam consumption, hence the need for massive evaporation, hence a massive boiler, hence idle axles to support a huge firebox, hence a gigantic tender, hence plants to supply coal en-route, hence immense coal stocks, hence diesel locomotives with a higher thermal efficiency (under test conditions) even if they cost twice as much and justify the Gulf War to supply them with oil.”©Ихнее всё Ливио Данте Порта.
tl;dr паровоз должен работать с умеренной нагрузкой.
