Raid healing 10's: to disc or not to disc, part 2

Raid healing 10mans:

Assuming the same skill level, assignment, and sustainability, when comparing the differences between the holy and disc on raid healing there's only two important metrics to look at: (1) Effective Healing per Second (EHPS) and (2) Practical Application.

(1) EHPS: the evidence from all the worlds public logs aggregated onto a single page of comparative data on EHPS shows no significant throughput differences between the two specs on the latest content -- i.e., WMO Top 20 Scoreboard for ICC10. 

(2) Practical Application: which spec is more effective in keeping the raid alive. Disc and holy heal differently and the majority position is probably that it depends on the encounter. I would disagree. As a general rule, preventative measures tend to be safer than reactionary measures; so in general, disc offers the more effective application than holy.

So, if you had to choose which spec to raid heal with disc should generally be the stronger option. It's throughput is just as strong while around 30% of it is the safer kind -- negative healing.

For further on disc vs holy, I have a more detailed write-up looking at this question for 25 mans: "Raid healing: to disc or not to disc."

How to Disc: the way of negative-healing

Preamble, why you should use disc as I say:
I'm going to use the Earth, Wind, and Fire achievement as an example of why you ought to operate a disc priest as I do in a raid healing situation. This fight is still challenging for most guilds and puts a ton of pressure on raid healers. It has massive raid damage including chain lighting, fire, smoke clouds, and raid-wide stomp like effects. These often happen simultaneously, producing a perfect storm of wipe and carnage. It's in such cases, which amount to the worst cases, where the disc priest needs to stand up as the raid's savior.

When various sources of inc damage overlaps, traditional healing, or positive healing, is at it's weakest point -- this damage model defines the Earth, Wind, and Fire achievement -- and it will overwhelm positive healers. Only preventative healing, negative healing, can hope to save the raid when all the elements do their worst. This situation is your reason for being.

My ranking for Earth, Wind, and Fire is not as important as my arguments herein, but as best in class on WoL for that achievement, or 18th overall regardless of class, you can be sure my advice here comes with decent enough qualification.

Application:
This guide is about as "all purpose" as you can get with healing at a high level. It applies to:

• Progression fights, according to my Earth, Wind, and Fire standing
• Farm bosses, according to my my Heroic Beasts standing
• Carrying extra weight, according to my Ony standing

This guide is not aimed at ranking on the scoreboard, it's aimed at healing the worst case. It happens that healing for the worst case brings out the best case numbers, and that stands to reason -- the worst cases demand the best performances.

Disc, how-to:
The first basic rule is a play-style point, it applies to any fight: never let a global cooldown go to waste. Overhealing only applies to positive healers, don't think like a positive healer. Unused shields (including DA procs) are much closer to unused fort buffs than overheals. So think of them as a insanely huge HP buffs which, if you can afford the mana, are never a waste.

The second basic rule is a gearing point, a proviso: never come to the fight unable to sustain the first rule. You need to gear for mana and regen. Your single greatest limit for increased HPS in a wost case scenario will be your sustainability, not your throughput stats. Even if you're on farm content remember that healing for the worst tends to bring out the best numbers, so apply this rule generally.

• The play style I use and recommend should have you going near oom on all fights, including easy fights like Heroic Beasts and Ony.

Final Word:
Follow the two basic rules that I follow and recommend. This prepares you for the worst, which is what matters most; and it should garner you some top scores.

This application is good for easy fights like Heroic Beasts; progression fights like Earth, Wind, and Fire; and for fail-recovery or pulling the weight of others.