While troop movement is simple to learn and easy to grasp it is also incredibly intricate. You can let your troops choose targets of opportunity or you can guide them through the course of a turn. Let's say you're planning on charging a machine gun nest. You've got a machine gunner of your own, but he's facing the wrong way. You also have two teams of infantry in place and between you and the enemy is a hedge. You can order your first infantry team to lay down some suppressing fire on the nest as the second team runs to the hedge and begins firing when they get there. The first team then runs to the hedge. By now your machine gunner has rotated and is firing at the nest. So now both infantry teams can rush the nest and take it out completely with (hopefully) minimal casualties. It becomes crucial that you coordinate your assaults as much as possible, but if you don't want to spend hours tweaking every order so it fits in a time schedule, you don't have to. The computer is fairly good at finding appropriate targets.