EDIT: As of Oct 19, there were changes made to our spells so the coefficient values might not be correct anymore. The tooltips are no longer accurate, so it’s back to the old fashion method. I’m leaving for Blizzcon Wednesday night, so I don’t know when I’ll be able to update this. I’ll try for tomorrow, but chances are it’ll be next week.
I jotted down my numbers for 4.0.1 and thought that others might want them as a reference. Feel free to double check my math.
46 mastery rating = 1 point of mastery
1 int = 0.0075% Crit, 1 SP
WoW automatically calculates the range of each spell and displays it in the tooltips now (screenshots after the cut), so I calculated the coefficients by comparing the in-game numbers to the values on Wowhead.
Coefficients work like this: Base heal value + (Spell power*coefficient) = Heal output
Holy Light = 0.33
Divine Light = 1.04
Flash of Light = 0.77
Holy Shock = 0.69
Word of Glory = 0.22 (calculated for 1 point of holy power, assuming coefficient is independent of holy power points)