What I can only say is

If everyone is decently geared and your team have 1 BLM, it is quite a complete waste not to pull one more pack. 2 packs aren't any different from 1 pack, any tank/healer meeting the dungeon entry requirements can handle that - fair. But be it 1 pack or 2 pack, your BLM will still be F3>F2>F2>F2>Flare anyways. Might as well right?

I am fine with both single pack pulls and pull the whole damn street, but when the tank does single pulls with a BLM in store... I don't know how to feel about that.