heartsong vs powertorrent

[Scraggie]

I ms holy and os disc/shadow and currently my enchant is heartsong because of the uptime and as holy with increased spirit. But was wondering if its time for me to switch it power torrent. What are all the other holy priests doing? I'm gonna assume power torrent just want to know the major difference on how it will effect my mana regen/throughput difference

[Kelesti]

the regen difference isn't that big, but the throughput difference is. The math is pretty straight forward too.

Power Torrent is has a 45s ICD with a 33% proc rate. That's a proc every ~51s (at 2s per cast) for a 23.53% uptime or 117.65 Intellect on average or, accounting for the 5% from Kings/MotW and 5% cloth bonus, 129.71 Intellect on average.
Heartsong has a 20s ICD with a 25% proc rate. That's a proc every ~28s (at 2s per cast) for a 53.57% uptime or 107.14 Spirit on average.

So, assuming some mid-level raid gear of about 5200 Intellect and 2800 Spirit, then the regen difference is ~70 MP5 without timing SF + HoH, and if you can time them in a six minute fight, that brings the difference down to ~50 MP5.

In short, you're trading 50 MP5 for a 500 Int proc which works out to ~ 130 SP on average. Now, sure, procs are worth less than static bonuses for healers, but what are your throughput alternatives if you were to trade that 50 MP5 for other stats? It would be roughly 50 Haste/Mastery. So, tell me, is that proc that is slightly more than 1 PPM for ~ 130 SP worth 50 Haste/Mastery? Hell yes. Considering that SP is a better thoughput stat point for point than either of those, then it works out to roughly 3x the throughput on average, which definitely more than makes up for the disadvantage of being a proc.

Now, obviously, if you aren't at the point where you can spare some regen, then Heartsong is going to be necessary. However, if you're regen capped or simply looking to trade some regen for throughput, since this is one of the few places where Spirit can be traded for Intellect rather than Haste/Mastery, it just makes more sense to swap to Power Torrent over Heartsong before looking at reforging Spirit.

Bringing this here, and closing it off.