[Neus]

This used to be the case but it changed with the Great Reckoning update, mainly to try to minimize the overhead with the stat lookup proc. Pretty much everything except base stats and item bonuses behaves this way nowadays. That said, I do see why this could be undesirable and somewhat annoying, so I could see the maximum FP proc taking the current Essence value into account, even outside of battle (so it doesn't jump up when you get into battle).