That seems a very plausible scenario to me. I mentioned Sleigh posted something about it before:

Quote Originally Posted by Sleigh View Post
WHM looks to be getting some buffs, but I have to agree with Nihility, there is only one safe and secure healer in my mind and that'd be SCH.

Supervirus, which has ranged from just regular Virus to the only thing standing between the group and death due to iLVL? Check
Can DPS while directing very generous, unhampered heals at the boss's target? Check
Can AoE better than half the cast of jobs by spending 7.5s and one Aetherflow to set it up for the next 20s? Check
Adlo for the ability to virtually negate the next tank killer if it crits? Check
Selene massively boosting raid DPS for free? Check. We've dabbled in dropping SCH for solo healing in the past and it rarely pays off well, SCH DPS + Selene buffs are damn near a DPS by itself. Technically even stronger in 3.0 due to SS buffs
If needed, completely free, strong raid heals/buffs from Eos? Check. It's hard to notice how good Whispering Dawn really is until you try solo heal SCH and realize WD usually heals the whole raid almost to full by itself, usually well before next mechanics (situational).
Possibility in 3.0 to crit Adlo the raid before a T9 Megaflare/T13 Gigaflare type of attack? Check check check

I do not know which healer will prove dominant of WHM or AST. Probably will lead to personal preference mostly, maybe WHM for progression, maybe AST for speed runs since presumably higher group DPS, who knows? But I know SCH isn't going anywhere.
With 2.0-2.5 content, White Mages and Scholars fill each other's weaknesses perfectly fine. White Mages take on the greater share of healing where Scholars assist when needed while off-dpsing. With the raid meta anyway. But whatever edge White Mage had over Scholar when it came to Healing, in particularly AoE healing, will be patched up in Heavensward. White mages on the other hand:

Quote Originally Posted by Lyrica_Ashtine View Post
Square-Enix has the right mindset by giving White Mages more options to deal some damage. Mitigation aside, healer DPS is another task for Scholars in raid environment (or minmaxers in general). To off-set this, White Mages are getting more tools to theoretically close the gap on Scholars in this field. Whether it's equal or better will depend on the potency of each spell they'll be getting in HW.

However, this does not solve one of the main reasons why White mages aren't off-DPSing as much as scholars are: Accuracy. As long accuracy is a problem, White Mages will never be able to compete with Scholars in this area. With or without the new spells, especially when the accuracy requirement becomes higher and higher.

It's not like the new spells/abilities White Mages are getting are bad. They're bland, if anything. The damage abilities are just not very viable as long accuracy is a thing.
For the record, Scholars will be getting:
Indomitability - AOE Heal (Aetherflow required to cast)
Deployment Tactics - Gives Adloquium and Eye for an Eye to party members near the person they are casted on.
Emergency Tactics - Changes Adloquium from a shield to a pure heal
Dissipation - Consumes Eos or Selene for 50% extra healing potency (Currently overpowered, will be adjusted before release)
Unnamed Spell - Non Elemental Magic attack

White Mages will be getting:
Asylum - AoE Regen Bubble
Assize - AoE that does Healing and Damage at the same time
Tetragrammaton - Instant Heal for 50% of target's health
Stone III - Will Replace Stone II as main DPS skill
Aero III - AoE DoT