Merry Christmas Holy Paladins!
Anyways for Christmas, I bring to you the my first look at holy mastery in Cataclysm.
This is data taken my PuG Heroic Vortex Pinnacle. I don't have raid data yet.
Here's what won't proc mastery:
Protector of the Innocent
Healing from Seal of Insight
For my spreadsheet, please see: https://spreadsheets.google.com/ccc?key=0ArLmeVrNbnLxdExWd3hHb1d4ZmcwSUFiVTJXN25NMWc&hl=en#gid=0
I make one very important assumption. Shields are either completely consumed, or completely wasted. I do NOT account for partial consumption of shields. This is significant because we start with 10% base shielding. For example, if we have 16% shields, but only the first 10% (10% relative to the total heal, not 10% of the shield) are used, then the last 6% due to rating are completely useless. However, because damage is very high relative to shield sizes, I'm going to assume that shields are always completely consumed when a shielded target takes damage. Without this assumption, mastery is devalued.
So including overheal, 48.47% of my TOTAL (not effective) healing allows for mastery to proc. This ratio is likely to be lower in raids because Holy Radiance is likely to be a bigger chunk of your healing. Your playstyle is likely to change this ratio as well.
Next up, if all of my shields were used, I would expect to see 555534 shields used. In reality, I saw 337760 shielding used. So that means, of the shields that occur, I expect to see 61% of them used.
So while the tooltips suggest 179.2 Mastery Rating will produce 1.25% extra shielding, this data instead predicts it will do ~0.375% extra shielding (0.5 healing that allows shield * 0.6 ratio of used shields).
This suggests that crit is better than mastery for average boost (due crit being RNG) to HPS and HPM. This however, does not account for additional benefits that crit provides in the form of Conviction and IoL procs.
DO NOT READ THIS AS MASTERY IS USELESS. Because Mastery and Crit stack multiplicatively, there is an ideal ratio to keep the 2 at. I'll get into that later after I confirm these findings in a raid setting.
TL/DR: Mastery operates at 30% of the tooltip effectiveness.
Edited by Lylthe on 12/27/2010 2:59 PM PST