My response was so long that I couldn't actually reply, so I had to make a new post. This next series of posts are in response to Apoktenio's comment on my "Change is is the wind" post.
Such a great comment...Going to have to leave multiple replies just so it's not jumbled...
First - the mp5. GC has said numerous times that they want to make mp5 more attractive - and that Illumination, combined with Divine Plea and replenishment, may be too powerful. MP5 was put on our gear in Ulduar because the Devs thought we'd need it after the nerf to DP (50% healing debuff) - with the thought that if we had mp5 we woudn't stress about the debuff and might not use it as much.
The issue comes to light when you look at the mana returns int/crit give vs mp5 - even with the DP penalty. For those 15 seconds, if I need to, I can pop a haste trinket/gloves and still have smilar throughput, even if the base heals aren't as large. More heals going out, equals more crits, equals less cost. I'm going to test this tonight, but I'm fairly certain that the mana return while using Divine Illumination is still based on the original healing cost. I'll get solid numbers on this tonight and post on it tomorrow though (add in the mana reduction of 4pc).
I'm going to need more paper - but here's some math on what would happen if we kept on the same track as we are now - and replaced all our mp5 with int/crit. Hell, this math assumes no replacement as I’m going off my own gear.
Let's assume 50% crit - which isn't even close to out of the potential range given the gear I have and full raid buffs. Let's also assume (for balance) that we get a 1:1 ratio of crit and non crit. We all know that there's streaks of both - but let's suspend reality for just a moment.
Note - for this I am assuming the HL Libram of Renewal and the Glyph of Seal of Wisdom - putting base HL costs at 1098 and crit costs at 333.
At 50% crit - with enough haste to push our HL to a flat 2.0 sec cast (I know we can get faster, but for math this works better) we are going to expend 1431 mana every 4 seconds. Assuming a 22,000 point mana pool, with no DP or Replen (or mp5) - I will go OOM in 1 minute of solid casting.
Now - if I DP at 15 seconds in, I'll return 25% of my mana, so I'll get 4,500 back extending my casting by another 12 seconds, just enough to push me into the next DP CD, buying me another 12 seconds of healing. I'm now at about 84-90 (depending on how much was left in the tank with fractions) seconds of non-stop push to you drop healing.
Replenishment, which even GC assumes will always be up, returns 3.75% of your max mana every 15 seconds - or .25% per second. So at 22,000 mana, I'm getting back 55 mps - or 275mp5. So every 26 seconds, I'm earning another four seconds of healing. Add that to our timeline above, and even without the fractions we're going to get 3 26 second replenishments - adding another 12 seconds to our healing, pushing us to almost 112 seconds, which is enough to get another full replenishment so we're now at 116 seconds - almost two full minutes, just by adding replenishment and DP.
Add in a strategic Divine Illumination and Divine Favor (you'll use that 2x in the illustration above) and you've now pushed your healing into another DP cycle - extending our healing out even further. Without going all EJ with the math and a simulator, I could easily see this pushing us into the three minute mark (more numbers tomorrow). At three minutes of solid healing - with no mana pots, just DP and Replenishment - we've cranked out 90 Holy Lights - for 1.125.000 healing - and that's not counting the two free crits we'd have.
I see a change coming – but I don’t know what it’s going to be. GC’s concern is that we can ignore every stat other than int and crit. Spirit? Useless. Mp5? Useless in it’s current setup. What’s happening now with Paladin’s is exactly the same thing that was occurring with DPS warriors in BC and early Naxx. They went for leather over plate because it had superior stats based on the way that warriors worked. This was one of the reasons they added Armed to the Teeth (gives AP based on Armor) – to make plate more attractive.
As long as our current regen abilities and in game mechanics (DP, Illum, Replen) are this good, we’ll continue to play within those guidelines. There have been some suggestions on making those abilities work off mp5 so that we find elemental shaman mail less attractive. I’m at the point where I’m wearing cloth because it’s better than my plate T8. Intellect is king, and so much so that the trinket off Mimiron (Pandora’s Plea iirc) which gives a flat boost to Int is quite possibly the BIS trinket for Paladins. I’m even working on a Greatness card – simply because popping DP when it procs will return that much more mana.
Check out this threat at MMO – GC goes through all the points and really does a great job (IMO) of explaining that mp5 shouldn’t be useless, but they don’t know what the fix is yet.