Don't you agree with me that it would probably take a really long time, and you would probably get lost, if you had to go up and down all of the mountains, as opposed to if you just drilled a flat tunnel that could go straight on through?
¿No están de acuerdo conmigo que probablemente llevaría mucho tiempo, y probablemente uno se perdería, si tuviera que subir y bajar  todas las montañas, a diferencia de si uno acaba de perforar un túnel plano que podría pasar directamente?