SCH vs WHM

[Kyomih]

snip

You should have adlo AND SS up on the tank and melee anyway for WW. Again, SCH/WHM = adlo shield and SS while WHM/WHM only SS.
There is hardly any situation where you need to have 2x regen and 2x medica up not to mention you can't sustain that for long both MP and enmity wise. Not to mention good luck with that combo for encounters such as T4 where you have to have enmity at pretty much zero for transitions. Regens are quite a tricky beast for end game content if you are not careful. Medica II and regen up while the sisters spawn on Garuda EX is also not fun.
Adlo and Succor plus SS means you don't have to start burst healing immediately and are less likely to pull aggro during transitions.

Not to mention SCH is just the better single player healer, hands down
Embrace + Physic + lustrate + adlo = divine