I did a little number crunching with havok's and howling twilight via update2.
On paper it seems if you have perma hasten and 2 SO recharges, or 4 SO recharges you can keep the howling twilight debuff on permanently. As a clickie, it would be pretty useful to decrease damage. (if anyone has the exact numbers for the debuff it would be nice to compare).
Anyway, using it on top of your darkest night powers the acc/dmg debuff stacks. That means the annoying stuns, that bother every toggle user would be alleviated by this power.
So I guess from looking at the numbers, i would slot 4 recharges with perma hasten, and 2 end reducers. That would put it at a reasonable 21 end cost, and a recharge of 55 seconds. Which basically means I can fire off 5 to 8 attacks before needing to refresh it, and most fights wouldn't last long enough to benefit from any increased duration.
I.e. You fight for like 20 to 30 seconds currently at most (a lot less with blasters) so having a aoe disorientate power available more often is a better option than having a longer lasting one shot. And recharges still make you able to stack the power. Ideally, I might say, 4 recharges, 1 end redux, and 1 disorientation duration.
Basically I feel like dark miasma would greatly benefit from a perma howling twilight state when update2 goes live it seems to at least be better than debuffing than the rad guys.
Hope that made sense for why we should slot it out fully, and gives hope for those dark-elec guys who want to blast a bit, but dont have the neat immobilizing effects, have no slot to spare for tar patch, etc.
Edit: And I remember the old thread talking about defense vs resistance, if you think about it this way, you may get a low debuff with Howling twlight as 10%, but even with 10%, that's 5 slots spared from shadowfall as a defense buff, and using those slots for dmg resistance.
Basically, while its a roundabout way to get your defense/dmg resistance, it seems pretty darn effective.
