Resto Shaman BiB Stat priority different than IcyViens

IcyVeins and the old Mr. Robot used to prioritize Crit above other secondary stats, but now it is prioritizing mastery. Why is this?

I am always running out of mana and my healing output is pretty poor.

Is there an easy way to change the stat priority, like just saying to rank them like so:

Intellect
Critical Strike
Versatility
Haste = Mastery

Mr Robot doesn’t work like that, the recommendations are based on the result of simulations.

It will get more accurate soon, it takes time and lots of computer power. There isn’t much point in doing that when you know that Blizzard will put out balancing patches soon.
Have you read the timeline blog post?

With mastery, your healing output will be high when you need it to be high. Our stat recommendations are based on our healing simulator, which right now is preferring mastery.

I’m going to make a new mythic+ healing script soon, though, based on some of the new dungeons which I have been testing out. Especially when our gear is low, mana is much more of an issue, but I’m not sure that Crit will necessarily be the way to go.