Originally Posted by
zakaluka
Why people don't renewspam, and why int > spirit?
WRT renew, It's pure numbers, and there are two perspectives you can take.
Spells have an HPM (healing per mana) value and also HPCT value. I don't have accurate numbers anymore, but at the end of t12 when I checked HPM values were Renew: 10, PoH: 16. Also Renew's HPCT value was about 20% below PoH's. Because Renew stops benefiting from haste, and never benefits from mastery, Renew's HPM/HPCT will scale much more slowly than PoH's will. All of that means: (1) if you had spent every Renew cast on PoH instead, you would get more total throughput (2) if you had cast PoH instead of casting renew, you would have spent less mana. Double whammy, you can't really reason yourself into renewspam with all that info. Renew is useful for spiking with precasts, also as supplemental healing on a tank with threat. That's about it.
On the other side of the issue, PoH is very precise - you can directly control how much overheal it does. Good priests get the overheal figure on PoH to below 20%. Renew is horribly imprecise - you have no way to ensure low overheal on renew, unless the whole raid is taking constant high damage. In which case you'd be best off to precast your renews before the damage, then switch to PoH since it does more healing per time anyway.
Int>Spi? Actually, spi's value depends on whether or not you OOM. But even then, how much extra healing a point of spirit will give you depends entirely on how long the fight is. Int will give you WAY more healing per point than spirit, even if you are running out of mana. The fight has to be longer than 12 minutes, and you have to be carrying an average heroic ilvl to be able to make a case otherwise. I simmed spi vs int against 4.2, and you can make a case for spi after you break ilvl 400 or so, on fights that are longer than 12 minutes. Only one fight this whole expansion meets this criteria, and in hardcore only.