Effects of the 2.3 Spell Damage Bonus for Healers

In the upcoming patch its been widely touted that healing gear will also start providing a partial bonus to spell damage. This change is intended to offset some of the woes healers had when trying to experience any other part of the game besides grouping. Having no damage output is a serious handicap when trying farm, grind, quest or simply survive on a PvP server. Most healers still have access to some damage spells when they are heavily holy/resto but their gear simply has no effect on improving their dps. What use is it to have a full set of Karazhan epics when it still takes you four minutes to kill a level 68 mob?

Now with patch 2.3 coming out one third of all +healing bonuses will also give spell damage. This means that a lot of healers will be getting a serious boost to their offensive spells. This should make it more easy to quest without having to spend a large amount of gold on talent build changes. Also as a side effect it should reduce the number of gear arguments between healers and dps classes. Since healers are required for raids they often gain DKP points a lot faster then other classes which sometimes results in epic fights, especially over weapons.

For an example of how the change to +healing gear will effect an average healer I'm going to use the stats of my paladin.

1450: Healing Bonus
224: Healing/Damage Bonus
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1226 Pure Healing Bonus

On average my holy shock spell does a minimum of 660 damage and I believe its base is around 540 damage

660 Average Damage done by Holy Shock
540 Base Damage of Holy Shock
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100 Damage applied to Instant Spells

Based on my 224 Damage Bonus I can assume around 45% of it is applied to my instant cast spells. Since paladins don't have any damage spells with a real cast time I can expect this bonus to be the same on all my spells. Of course spells with longer cast times get more of the Damage Bonus applied to it. Healers like Shamans and Druids will see a much higher increase on their spells like Wrath and Lightning Bolt.

Since my healing gear will give 1/3 spell damge I'll end up with an increase of 409 spell damage. Thus my paladin's new spell damage should be around 633 after the patch. Applying 45% of my new spell damage to my instant cast spells mean that I can expect my holy shock to hit around 825 after the patch instead of 660. This means that the change increased the damage of my offensive spells by about 25%. In general expect healers to be hitting about 25% harder then they used to before the patch. This could be especially important in arenas where healers will often throw out instant cast damage spells on stunned targets.

Calculations for New Base Damage
1226 / 3 = 409 Increased Spell Damage
224 + 409 = 663 Total Spell Damage
633 * .45 = 285 Instant Spell Damage
540 + 285 = 825 New Damage on Holy Shock

Calculation for Overall Increase
825 - 660 = 165
165 / 660 = .25 (25%)