Spirit provides mana regeneration only when out of combat so is it really worth it in raids or dungons? is it better to reforge it into more helpful stats?
It regens mana in combat too, how valuable depends on the spec. In *general* having some spirit is good.
Ahhhh this isn't BC we are playing....in MoP spirit in constant regen, you use to get regen from Int to, but they took that away in MoP, there is no MP5 anymore, no 5 second rule now a days.
Most healing classes have passives that increase the mana regen they receive from spirit while in combat, usually 50% or so, though in Cata (not sure about MoP), Holy Priests had far more regen in combat than other healers.
Spirit is necessary for all healers as far as I'm aware but the amount varies from spec to spec and your comfort level with mana. I'd research each class' spec specifically to find out the spirit breakpoints.
Healer specs get a passive that allows 50% of their normal spirit regent to continue during combat.
Spirit is the most valued stat for any healer for as long until you are comfortable with the amount of mana regen you have during encounter. The optimal amount is impossible to say because it depends on the person's playstyle and class but if you end up an encounter with close to 0 mana and you were not holding back because the lack of mana, then it's optimal.
To try to give you an answer that helps you understand it from out of combat regen; look at your spec core abilities. One of them will be a conversion % of out of combat regen (ex: continue to receive 50% of your out of combat regen while in combat). That alone tells you that spirit affects combat regen.
Now, you can do something else; exchange similar ilvl pieces, one with spirit, one without, check your character sheet ... notice how your combat regen changes.
I'm not subbed right now or I'd go in more detail; but be assured spirit affects regen. It has been a long time since the days of MP5 and downranked spells.
How much spirit you need depends on many factors. How geared and good at execution is your group. How good are the other healers? How good are you? Do you use spells efficiently or are you a mana whore even on easy to heal fights? If you are already efficient at spell usage, cd usage, and your group is competent ... you may need very little spirit compared to someone who has a bad spell priority, bad group, or bad overall usage of cds including mana regen.
You only need enough mana to not go oom by the end of the fight under the worst circumstances your group will put you through. Any more than that is wasted. If you finish with 50% mana consistently, you need less spirit and could move that stat into other ones appropriate for your class. If you are always oom or barely scraping by, you need to look into which stat to sacrifice for more mana/regen ... while also considering other options and how they affect your overall throughput (enchants, trinkets procs, etc).
Paladins are conspicuously absent from that list. Is there's called something else does anyone know?
Old Gods made me do it.
Seal of Insight + auto-attacks will regenerate a significant amount of mana - something no other class can do.
Using divine plea smartly along with seal of insight will allow most good holy paladins to play with less than 12k spirit, where a resto druid may want 20k in hc SoO gear.
Depends on your class and playstyle. I always figured you should have some spirit, which is why I'm generally ok with what GC said about it.
I heal things!
Is it a fox? Is it a dog? Is it both? All hail the foxdog!
Yeah people already answered this really but all healing classes get passive abilities that let them continue regenerating with spirit during combat.
So it is definitely worth it to have some, thought not necessarily on every slot.