Massive essence loss and i'd hope gods would discourage the use of their essence for the personal gain of their followers?

I mean it should cost more than two or three fully offered and killed astral node mobs.

That's why you have three people in an order bashing together... for example, Narsrim/Ekard/Diamante from Hajamin's, one link gets three... and should be able to tear through them quickly enough to recharge essence used. Unless you make it use 100,000 essence for 5 minutes, at least, at which point it won't get used. (Because it just freezes it, doesn't heal it)

Well as worded, it wouldn't even function on Astral. What it does is triple the rate at which you recover from insanity. On Astral, you don't recover from Insanity at all, which makes the rate of recovery zero on that plane. It stands to reason that because three times zero is still zero the power just wouldn't work.

The point of it seems to be making that recovery period less painful (perhaps making it easier to get back in the fight to protect shrines?), rather than dampening its effects while actually on the Astral Plane

And people in Orders of dead gods can recover in one third of the time, go back to Astral, bash, go back down, recover fast, go back up... No. Just no.