I am for real~ I swear, I'm not Akiza =p
You don't take a WHM only for Proshell, that was a strong and intentional hyperbole on my part just to invoke a reaction. As a healer main who plays both classes, I understand what the WHM tool kit brings to any raid and want to slap at SCH fanboy who thinks otherwise.
With that being said, I want to see Proshell being cross classed for class balancing come 3.0, and here's my rational behind it:
2.4-2.5 Raiding Meta
There are two healing slots, and two healers. WHM/SCH is the ideal combination for several reasons. (1) Their spells and abilities have high synergy. One handles raid heals, other can do single target heal. One has raw heals, the other has mitigation tools. etc etc. (2) You want to avoid stacking any singular class due the restrictions if has on limit break [this is a bit weaker reason, but valid]. Because you'll always wants WHM/SCH, the idea of "not having a WHM" will never dawn because of how the current raid meta is. Therefore, Proshell will always be readily available for any end game raid outside of a select niche of compositions.
Potential 3.0 Raid Meta
We have now introduced AST to the mix. There are now THREE healer choices for TWO raid slots. My assumptions on the 3.0 raid meta is based on current Final Coil meta (up to Turn 12) and the current skill sets of WHM and SCH, and knowing nothing about AST. The goal is to balance all three healing classes so they can be chosen for any scenario of raiding.
If neither SCH nor AST brings a 30min Shell-like buff to the party that stacks with Protect, WHM will be a favoured staple for any progressing raid because it effectively adds more eHP to the raid via higher mitigation.
I feel my rational for wanting Proshell as a true crossclass is quite justified.
Let's look at Final Coil
Heat Lightning, Cyclonic Torrent, Nerve Cloud, Flames of Rebirth, Flames of Unforgiveness, I imagine the explosion on Brand swap, are all magical in nature. There's no way SCH currently has the tools to provide a MDEF buff to every single instance an attack comes out. AST might, but I'm going under the assumption they cannot until we see otherwise. WHM provides a direct and free mitigation bonus to these attacks in the form of Proshell. Alternatively, this means more eHP.
Now, having not done T13 yet, I hear T13 is a HUUUUUUUUUGE HP check. What happens if you can't stack more HP? Then you add mitigation tools. Proshell provides, once again, a free mitigation tool that is applied once at the beginning of the fight and left there to do its business for the duration of the fight. This in turn provides a eHP boost to your party at no cost to the healer in the middle of the fight.
A healer's job is to prevent death and make sure the others can keep doing what they do best - smashing the baddie into the ground. Tell me, would you forgo a pseudo-permanent defensive shield for your raid, while you're progressing? If the HP checks remain the same as they are now, you'll want to stack as much HP / eHP abilities as possible to survive those checks. If 3.0 raids follow this trend, it'll be important for progression groups to level as many bonuses as they can for their group and Proshell will remain invaluable for that in the grand scheme of things.
This is why I feel it's important for Proshell to be distributed to ALL classes - to encourage healer balance. Without it, I feel raid groups will lean towards a WHM + other healer composition because Proshell is a free mitigation tool, which is the icing on the WHM toolkit cake.
Again, this wall of text assumes nothing about the AST abilities and takes assumptions on the current FCoB meta. My thought process may very well change once we see the 3.0 spell and ability list for all healers released.
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P.S. I enjoyed watching your banter with Akiza on the DPS forums, lol. Someone does have to do it eventually >.>;