Well, honestly I don't know how I can make you understand, it's the experience point of view, not something I can tell you with simply word.
Say for example. When I was in Infantry school, we did all sort of Tactical Simulation. When you run those simulation without anyone telling you anything in advance, you will almost guarantee that you will lose your whole team. Teaching ability coming from how people fight the war before you, it's DIFFERENT when it come down to different country, even when you are talking about the same battle, same war.
You cannot expect well, those experience you got from 50, 60 or 70 years ago and you can ignore them. You will still fall in the trap that have been using since WW2. As war itself do not progress as time progress, better equipment and advance technology only make you get there faster, it does not guarantee it will make you get there.