>it is fairly easy to make the gauge narrower by removing the nails and placing them back at a narrower position, something Germany did during WWII This doesn’

>it is fairly easy to make the gauge narrower by removing the nails and placing them back at a narrower position, something Germany did during WWII This doesn’t sound like it stymied the Germans much. Also look at the answer here: https://history.stackexchange.com/questions/23616/what-did-germany-do-in-world-war-ii-about-the-different-rail-gauge-in-the-soviet https://history.stackexchange.com/questions/23616/what-did-g... Do you need anyhing else to get convinced?