One remarkable development is for sure the firearm. This changed the battlefield forever and melee combat lost it´s relevance more and more. Even here you can see the change from the formations of line-infantry to ranger units (Jäger, Chausser, etc.) as the rifles were becoming more precise, reliable and cadence increased. Now we are in the present and the state of the art in infantry tactics are SOF, starting to develop in WW II. When Skorzenzy had nothing than a bunch of daring men (of course battle-hardened then), a Jaegerkorps soldiers schedule might be very down to the point until he is ready for deployment. Again humans want to structure their world.