As someone who used Call of the Sandman in Salt Crystals on my earth/savage dominator, I'm completely baffled by this change.
I don't want to feel like I'm being negative for the sake of being negative here, but I do want to share my experiences with the proc:
Salt Crystals is largely seen as a skip power on almost all earth builds, and for good reason - most aoe sleeps are terrible, particularly in team situations. My experience with the power slotted with this proc, is that if things are utterly dire, sometimes, if RNG likes me, it functions as an emergency stop-gap heal on a long recharge that might buy me a couple seconds for an actual control to recharge and properly handle the situation.
Best case scenario, I was typically looking at a 15-25% heal when and if it decided to cooperate, and that was firing it into the middle of 1-2 large team groups. The heal, individually, is so minor that unless you got lucky with a big set of hits it was hard to even tell if it had even activated, and even then, a lot of the time it wasn't enough to stop a squash anyways. If it becomes single use, the effect becomes so anemic that you may as well change it to something entirely different than it is now, because that slot would be better spent on just about anything else.
I'm not sure who this change is for, but I don't think I've ever seen anyone complain about this IO, and honestly, in terms of things that you can do with various combinations of IOs and powers, I'm not even sure how this got on the radar, it just feels weirdly and arbitrarily punitive for the few people that already picked these 'bad' (aoe sleep) powers, because the IO almost, if you squinted right, gave you a sort of reason to maybe take them.