Fey Light in FCoB

[Staris]

It is mathematically impossible for 0 cost haste to ever be a dps loss. You don't have to play peon. you can just postpone your attacks for tp.
Even if the dps sit there and don't attack because your they are completely out of tp, you still did the same number of abilities (at a minimum per time). Chances are you did more abilities than without the haste, and more within buff timers (if your good), so in the real world it is always dps gain.

The potential for loss comes at the opportunity cost of not using eos, which makes a dps loss is possible (per the amount of dps the SCH/WHM do). However, it is highly unlikely to ever be a loss, and far outside the realm of understanding for most individuals.

[technole]

It is mathematically impossible for 0 cost haste to ever be a dps loss. You don't have to play peon. you can just postpone your attacks for tp.
Even if the dps sit there and don't attack because your they are completely out of tp, you still did the same number of abilities (at a minimum per time). Chances are you did more abilities than without the haste, and more within buff timers (if your good), so in the real world it is always dps gain.

The potential for loss comes at the opportunity cost of not using eos, which makes a dps loss is possible (per the amount of dps the SCH/WHM do). However, it is highly unlikely to ever be a loss, and far outside the realm of understanding for most individuals.

That is pretty much it, and to put it simply "the damage has already been dealt" and it's always a DPS gain. It does help to have a NIN or DPS that can use Invigorate at the right time for those heavy phases like T11 adds.