Elemental shammy... NS + EM at same time?

[Skaarlaw]

well yeah, just respecced elemental and at first it seemed that you couldn't combine Nature's Swiftness (instant cast) and Elemental Mastery (100% crit) at the same time, 1 would black out before ic ould cast it

But then... later on in the day of playing elemental, i notice that i can?

I was wondering, is the first or second bit a bug?

Can I use Elemental Mastery and Nature's Swiftness at the same time, as intended?

That is all