Medica II

[Anova]

Medica2 has a HoT effect at the end of it, which is very useful when the entire party is taking damage. 2 Medicas is actually more healing power than medica2 (even with the HoT), but you will have to stand still to recast the 2nd medica (and it doesn't heal the tank more either during the extra cast time). Some fights have movement or damage mechanics that make the 2nd cast difficult or impossible to do without putting yourself or the tank at risk. An example is Titan, where Medica2 is often used to offset unavoidable damage from stomps so the WHM can top and stoneskin the tank in preparation for mountainbuster, or run to escape plumes.

Essentially, medica2 is a good heal-and-forget spell which lets you focus on single-target heals or dungeon mechanics. You'll use medica the most often, and only use medica2 and cure3 for specific situations.