im not sure if its already figured out so this is by theory. when you have lets say 100 physical defense you double it to 200 and divide by 10 to 20 and make that a percent. therefore you would take 20% less damage. so if you had like i think the most you can have in NG is like around 400 so you could get 80% less damage.
just my theory so i wouldn't be surprised if someone disproved me
just my theory so i wouldn't be surprised if someone disproved me