You can control their movement, which is critical, because they take actions whatever direction they are facing. A more foolproof method is to have them Mimic a character using Math Skills, because those work independant of position and direction, with no charge time.

A party with 4 Mimes and a character with Math Skills can pretty much clear the board without moving, and you only have to input the calculation once in every five characters. I prefer to input every command manually, but that's just my playing style.