Summoner's MP issues

[Yenn]

Everyone runs out of resource (except BLMs).

What are you actually trying to change?

Either:

1. resource is no longer a problem for anyone (I'm a fan of this approach).
2. deal with it.

I dunno why you think this is a problem only you have encountered.

Also, insulting people is really not a very good way of getting them on your side.

When a melee runs out of TP, their next Invigorate fixes it for quite a while.
When a SMN runs out of MP, our next Aetherflow lets us put up exactly one set of DoTs, but doesn't sustain us to our next Aetherflow. Even if we use Energy Drain x3 (which massacres our DPS), we can't sustain a rotation until the next Aetherflow, or even close to it.
Once we hit the point that we're OOM, our DPS drops off hard and stays low until the encounter is over or we get a Ballad.

Again, in the case of Twintania, a Ballad isn't going to happen; the BRD will have used all of his MP on Foe Requiem once the final phase hits. If he has to save MP just for the SMN, then the SMN is weighing the group down where a BLM or different class wouldn't.