Lets say you are a Mad Sheep. You're tough, you're mean, you put people to sleep. Now it's time to subjob.
Elephant would be a good subjob right? The whole Trample effect is a bonus and never forgetting could be handy.
Shark would also kick ass. Instant theme music there!
But do you choose these? no. you chose:
You are so pretty now. So delicate. People look at you and go MASH MASH MASH MASH!!! YOU DIE NOW YOU SHEEP BUTERFLY! MUH HA HA HA HA HA HA HA HA!!!!!!!!!!!!!
Although the initial use of this term was strictly for WAR/WHM, the term can be generalized towards any player that uses a subjob that offers little to no practical use to its paired main job; for example, the less common WAR/RDM that has even less MP and later spells.
The 5th Vana'diel Census reveals that the Warrior/White Mage combination has fallen to below 1.74%.