Both formulas are the same theoretically, but yes yours is the mathematically proper formula without taking into account Parry chance like neither of us did.

However, even when glyphed for using CS is always a mana drain, so it is pointless to add in SoI regen unless you add it in as a chance per CS attempt, or as an average mana per Holy Power cost when using CS. Where Holy Shock would be at 8 HP per minute at 8% base mana, CS would be at ((100-(8-x)-d)/100)*14 HP per minute at 10-((Weapon Speed/4.0)*4)% base mana, depending on how you factor in SoI procs. Maybe something similar to how you have melee with instant casts coded?

This also brings up another question, if the Seal of Insight proc chance uses a normalized weapon speed or actual weapon speed- I assume it is the former.

SoI behaves exactly like SoL and SoW did in that it's 15PPM. Using a 4.0 weapon guarantees the seal will hit, while anything faster than that will be proportionately less. A 2.6 speed weapon for example will always have a 65% chance to proc SoI per swing.

About 10 man heroic nefarian, I don't see the point in reforging full mastery; the only way a people could die in p3 (except tanks) is if it's not topped when the crackle happens, wich would be a big healing failure.
There was a bug on our first kills that caused peoples who ended their mind control right before the crackle to not have the nature resistance buff for a few seconds, letting them eat the full 130K+ electrocute. However it didn't happen on our last kills, so I believe it has been fixed.
You should better use your mana on the adds tank with your beacon on the boss tank or vice versa, and assist on the raid rather than trying to put little shields while doing a lot of useless overhealing.

Well, There was one change that wasn't on the notes and thankfully it isn't a nerf. Mastery now stacks up to 1/3 of the player's health.

Mastery may be more valuable but now it basically cements our spot as a tank healer which is a pretty bad position considering we will never get a spammable healing move. It is good news that our mastery can no longer be absolute rubbish imo.

New PTR Build seems to have a silent change to our Mastery - it's stacking! yay!

Stacks exactly to 1/3 of our current Healthpool, so up to about 45k Shields now, about 50-55k in Firelands I guess. Completly independent of Mastery Value.

Unfortunatelly Glyph of Divinity seems to be fixed, providing only 10% max mana now.

Let's hope that will make it to life

Played around with it for abit, capped at 1/3 like you said and any additional mastery does not increase it. Just attains the 1/3 health faster.
edit: Is it the casters health only and not the targets? Server just went down but that's what it seems like from me running around stormwind healing random people. Assumed it was unless it was just showing incorrect amount.

Definitely looks like it is based on caster's health. I tried it on a few people in SW and the cap is the same regardless of who I am casting it on.

I don't see how that makes mastery any more desirable than it is now, since we can just spam heal someone and stack to the same amount we would otherwise. We're better off focusing on crit. I think it's unlikely things will stay that way.

*edit* - Just to clarify, the stacking itself isn't the problem, but how mastery scales doesn't make sense. It should be shifted to something else, like the max value of our shield, or interact with some sort of diminished return on the shield stacking.

Max value of the shield will only matter if there are 10 second pauses between damage. It's hardly important, other than just knowing what it is

The cap definitely isn't an issue in raiding environment despite the amount you can pre stack before entering Combat on your tanks.

I don't think it will change our prioritizing in a way that Mastery outperforms Haste. Regarding Crit it sure has to be further evaluated - on current PTR Tests Illuminated Healing made up to about 10-13% of my overall Healing depending on HR Usage. This of course is a Boost, compared to the about 8-9% on life it currently does, that is not only caused by the change to Mastery Rating Scale.

However, since Mastery also benefits from crit I really have doubts that it will outperform it, as both our Beacon Heal, as well as our HR, so about 30% of overall Heal, don't benefit from it. This however sure needs further mathematical evaluation.

On live, I have about 130k HP fully raid buffed, and I also have 103 Mastery rating (.57). My most recent WoL shows my average DL hitting for about 24k.

12.85% of 24k = 3084
33% of 130k = 42,900
42,900 / 2056 = 14 Divine Lights to reach the max

My theory would be that mastery might be useful up to a certain point, where the goal would be to get the number of DLs to reach the max within reason. With haste and the boss swingtimer, you *might* be able to land 2 DLs on a target before each swing, which would then eat the full shield, and you would have to start over.

So even with the cap, if this proves to be the buff our mastery needed, mastery would still be a desirable stat up to the point where 2 DLs = cap, which would be quite unreasonable to hit.

Edit: Fixed some numbers.