When any spell is forced to be multitargeted and it targets the characters, the damage dealt is always 1/5 the possible damage (in other words, the split damage modifier is always 5).
This explains why the Medicine command behaves the way it does and how enemy magic is dealt to your characters.
If the Medicine command had optional targeting (one target/targeting everyone option) instead of forced targeting, Medicine would heal better.
In the Elementals battle, if Rubicante casts his Fire2/Fire3/Glare attack onto 2 to 4 living targets, it would be the same as having all 5 characters be alive for the attack.
The split damage is always fixed at 5, despite the number of possible targets on the field (except for the solo character). An improvement on this would be to count the characters on the field (minus those that are in Jump or Hide status) and readjust damage accordingly.
However, unlike Medicine, when there is only one target, the split damage is reverted back to single targeted damage, just like the rest of the FF SNES series.
We have EVEN MORE themes now, but some old ones are gone...