To say again. 50% mastery line is BS. Going from 45% to 50% mastery is a 3.45% increase in output on a 0% health target, vs 50% to 55% mastery is a 3.33% increase in output on a 0% health target. There is nothing magical about 50% mastery.
Overall. Have you ever calculated how much stats increase your / your raids output?
Based on my calcs... 1 int provides me with as much output and 1 spirit provides me/5 other healers. That's before this legendary meta gem made the other healers start asking... why does mana tide matter?
Which means... Heroic Horridon's trinket is BiS by such a huge margin I can't even begin to pull my hair out.
My thoughts on all BiS lists like this have always been... I'm sure when it matters, and we are trying to kill heroic ra den for the first time... I'll totally be rocking multiple ra den items (: I always prefer stat weights (#'s not priority) @ an ilvl and specific haste breakpoint.