it's an idiom. of course it's not needed because there are more ingenious solutions to the energy consumption problem and crosswind stability. for example rec

it's an idiom. of course it's not needed because there are more ingenious solutions to the energy consumption problem and crosswind stability. for example recuperation of break energy. thus you can build slightly heavier trains which withstand side winds despite the slightly narrower standard gauge, which again allows you to buy internationally, further saving costs and further benefiting from energy saving innovation. bY using an unusual gauge they painted themselves into a corner (another idiom) as they can't easily sell old material on and buy newer BART cars.