It's true that to move and navigate effectively you have to be super familiar with that style of environment. You have to be planning your route from what you

It's true that to move and navigate effectively you have to be super familiar with that style of environment. You have to be planning your route from what you can see no more than a dozens or perhaps a hundred metres ahead. And thick clothes really helps. It clicks when you realise you can just push through a lot of stuff. Its the kind of thing that soldiers get sent on exercise to learn by immersion. Of course the early humans would have been probably as in-tune as the best trackers and bushcraft survival experts today, and hide makes really good clothing.