NTTE is kinda a low damage PR, though. Sure, you'd have continuous DPS on him, but would that add up to be greater than 9 shots from Sleeper? I've not had a go at the new raid yet, so I'm not 100% sure what the situation is leading up to a damage phase, but if there are a bunch of adds, NTTE probably isn't the best place to use up your exotic slot, either, which would mean that you'd have to switch things around and potentially lose ammo.