The pressure system is completely broken, it only functions correctly maybe half the time...
Pre-launch when the pressure system was introduced to us, they said that you wouldn't begin to feel the pressure effect until you were drained of stamina...which makes sense. You shouldn't be nerfed until you're, well, nerfed. Unfortunately that's not the case as you can have full stamina, but your attributes get nerfed by a rough guestimation of 65 to 75% and get all sluggish and slow...DESPITE hvae stamina to burn.
They rushed this system without properly testing it and it's rendered the game damn near unplayable.