Can someone give me an in-depth explanation why Summoner is arguably the worst DPS?

[scarebearz]

Apocastatis is an extremely good spell for progression, clever use of Manaward and/or Manawall gives Black Mages a distinct advantage on damage heavy phases and Flare as been useful on quite a few occasions. All of these
tools are not available to Summoner whatsoever. Having Summoner slightly better in single target than Black Mages (around 3-5% higher) while keeping Black Mages the respective king of Burst/AoE would be a fair tradeoff and
would by no means invalidate the use of Black Mages. That argument, which has been brought in this very thread before is nothing short of being overly dramatic.

When SMN's did more dps than BLM in SCoB, BLM was a poor choice for any serious raid group and many BLM had to play SMN. Was this needed to kill T9? no, but it helped a lot of raid teams get the kill quicker. I don't think it's being overly dramatic, I think SMN and BLM should be on equal footing potential DPS-wise for FCoB. BLM has some good utility, but SMN has s bit better utility.

Nothing personal but I have difficulty being told by a class which ressources are theoretically infinite what the scale of the buff should be.

The "infinate resourses" thing has been brought up over and over again, does this make BLM do excessive DPS? no, in order to keep going we sacrifice DPS, just like SMN has to do in longer fights. It's the potential DPS of the class that matters, not the different class mechanics.

Funny thing is, melee are that much better dps-wise that we casters are mostly fighting over 1 raid spot, for BCoB I remember 2 casters being much more common.

[Dwill]

When SMN's did more dps than BLM in SCoB, BLM was a poor choice for any serious raid group and many BLM had to play SMN. Was this needed to kill T9? no, but it helped a lot of raid teams get the kill quicker. I don't think it's being overly dramatic, I think SMN and BLM should be on equal footing potential DPS-wise for FCoB. BLM has some good utility, but SMN has s bit better utility.

You can't be the king of AoE and nigh on-demand burst then ask for the same equal sustain single target than someone who can't AoE has well and as a bigger ramp up time to achieve similar damage. Summoner being slightly ahead (by 3-5%) is a fair trade. And we'll agree to disagree on utility.

The "infinate resourses" thing has been brought up over and over again, does this make BLM do excessive DPS? no, in order to keep going we sacrifice DPS, just like SMN has to do in longer fights. It's the potential DPS of the class that matters, not the different class mechanics.

Funny thing is, melee are that much better dps-wise that we casters are mostly fighting over 1 raid spot, for BCoB I remember 2 casters being much more common.

Melee issue aside (which I agree with you), your resources doesn't make you do excessive damage but it also means you can keep doing the same damage indefinitely whether it's 2 minutes in the encounter or 10 minutes. For summoners, the longer a fight goes, the more you have to throttle which means you have to kill your damage ( stop Ruin II weaving and start using Energy Drain over Fester) to be able to keep on and even then, there is such a point where you'll go so low on MP that the damage output will be much worse than other jobs. There is a reason people aren't particularly fond of Summoners on T13.

So I stand by my statement, Black Mages have no say nor any standing ground on the MP management issues versus Summoners.

As someone else said, Manaward and Manawall are not exactly "party utility", they mostly just let the BLM survive/eat certain attacks to allow them to move less. (i.e. allows the BLM to keep up their DPS)

Apoc does have party utility, but it's not used/needed very frequently, I'd much rather have super virus or an in combat raise!

Why does a skill need to be "Unique" to 1 class to make it very useful?

As it has been stated multiple times already, having an instant raise for Summoners isn't that much for a utility considering that healers will always have priority over Summoners to use it. If you reach the summoner's raise, it's more often than not a wipe. And for Supervirus' case, it's mainly used for Nerve Gas and Giga Flare and it is handle by the Scholar.

I would take Black Mage's survivability tools over "utility" that his better handle by other jobs to begin with.