And NS lets you insta-cast GW. The shield bonus is okay, but it's just phys and you're making it sound like it's +5% dodge.
I don't think there'd ever be a realistic scenario where you would ns-gw, so that's a moot point. And if you did, you'd be sacrificing that selfheal you're hammering on constantly.
You only need maybe a tenth of a second (if you're slow) to NS+GHW yourself back up as resto. You can actually heal yourself mid-combo with NS.
You're not gonna heal yourself midcombo in a rogue opener cause it doesn't let you.
A mage can currently burst you down during a 4 sec blanket silence in which you can't heal.
I'm not gonna sit here and say NS is bad or worse than EW, but it's not worth giving up so much for.
I was def wrong on the math there, been awake too long to do any of that right now.