My most common uses for swiftcast:

1. Applying stoneskin while running from one trash pack to the next in coil or ak/wp
2. Battle rez
3. Medica II on ADS for missed silences after everyone gets hit by paralysis.
4. Medica II on garuda if one of the adds is pointed at the raid doing massive damage to all
5. Using it to instant my first Holy as I run in to holy spam for wp/ak/coil trash
6. Applying stoneskin to the tank during Titan if I'm needing to move
7. Trolling the tank by casting Medica II right as he's going in to pull a boss.