It can stack up to 4 and even proc again at 4 stacks but will only refresh that stack when it happens. Cannot stack to 5.
Getting it to stack is pure luck. I commented on this a while back:
Originally Posted by
Venara
It's so random though. Sometimes I get a return of only 30-40k mana and other times it's as much as 150k mana (~8 minute fights). This is in fights where I do literally nothing but either regular healing without pause or Atonement healing without pause. I've tested both extensively and the return is very shaky. The good results come pretty much all from fights where I was lucky to have the trinket proc stack.
It's still a great trinket but there's no reliable way, other than chain-casting, to get it to stack. Often you'll get another proc just a second after the first fell off. Simply bad luck, I'm afraid.
Here's a few numbers from last night and last week. I'm healing mostly with atonement.
Code:
Boss Mana Fight Mana Fight
Jin'rok 20625 03:18 56375 03:35
Horridon 78375 08:55 96250 09:19
Council 108625 06:26 75625 06:39
Tortos 42267 04:42 59841 05:42
Megaera 94875 07:23 63250 08:12
Ji-Kun 110000 07:02 123100 08:58
Durumu 95342 07:45 112750 08:52
Primordius 71440 07:24 74250 07:57
*Edit* I have the LFR version at the moment. Normal won't drop :S So these are numbers from the LFR version.
Source:
http://worldoflogs.com/reports/ccibmqsqphuku46z/
http://worldoflogs.com/reports/1377i39b77vers36/
http://worldoflogs.com/reports/3q14jliifbgpa053/