User blog comment:YourPrivateNightmare/Discussing the new defensive mastery tree/@comment-973379-20150626081219/@comment-5077844-20150626085813

i think it doesn't make sense, because it only really gives you a ood amount of Mr when you have loads of armor, which you only have if you don't need MR anyways, so in most cases the bonus will be one-sided and not to big.

If you, however, put that point in Enchanted armor, making it at least 7,5%, you are guaranteed a nice bonus regardless of what you build