It's important to remember that applying one or more stratagems significantly slows down the coming spell. While not relevant for a planned AoE sleep/gravity or an Ebullience-ificated nuke, but it's a very important thing to consider when looking at most of what Scholar casts in Light Arts or an emergency crowd-control spell.
Switching Arts and using the corresponding Addendum isn't an instant affair, either. It's just one or two extra seconds and one Strategem charge, but that can be an eternity or one charge too many in some situations.
Also, saying a job is second in curing to White Mage is like saying Mars is the second most livable planet in our solar system. The statement is true, but good luck building a mountain retreat on Olympus Mons. Scholar and Red Mage are on pretty even keel as far as healing goes, with Scholar's only palpable advantage being native status cures rather than status cures from a support job. If that's even an advantage.