You raise a lot of good points, and I'm always glad to see some non-orthodox thinking.

Ease of use is a big part of the attraction. It factors into my recommendations to novice players all of the time.

A lot of players dislike "tough" levels such as compounds, devilite offices, and greaver arenas because these players are overly reliant on certain tactics (brandish charges, pulsar shots) and unaware of other tactics (bombs, flourish first strokes). Based on your posts here and in earlier threads, I suspect that you agree? Insofar as it raises awareness of other tactics, your thread may be useful.

I agree that "REALLY" is vague and hides a lot of the disagreement. So I'll try to stick to more concrete points.

The "orders of magnitude" is quite an exaggeration, if you truly mean powers of 10. Perhaps you don't.

Dark Retribution is very powerful. But suppose that there are gremlin menders in the fight. Unless you do something to suppress the healing, DR kills them and the monsters around them slowly. So you have to let them shield, kite some monsters away, kill those monsters, come back, kill the menders slowly, etc. In contrast, an Acheron charge (or Obsidian Edge, Umbra, Grim, Callahan, ...) can kill one or both menders instantly. Then you kill the rest of the monsters. Maybe I'm bad with DR --- despite using it frequently --- but I find Acheron faster in this common scenario.

Yes, a haze bomb is better than a brandish at spreading status. And a blast bomb is better at knockback. And DR outputs more DPS against a crowd, say. But while these functions are orthogonal to one another, there is no reason why a tactical situation shouldn't warrant a combination of them. What if I examine the fight and say to myself, "Ideally now I would inflict a bunch of damage while knocking these monsters out of my face. And some status would be nice of course." That goal may seem contrived, but actually it is quite typical, and a brandish fulfills it better than DR or a haze bomb, and often better than a blast bomb too.

Rather than using a Brandish for its absolutely astounding damage or its support role that it can fill, there's also the point of using it for consistency. Not consistency in terms of "it can do this over and over", but consistency as in, in any situation you throw it in, it will excel. In contrast to your argument of "all things that replace something that combuster was doing for you- which raises the question as to why you even need combuster", there's also the argument of why bring all those things when you can just bring Combuster. Ignoring the fact that some people are limited by open Weapon slots or major access to many crafting possibilities, a Brandish effectively gives you many weapons in one, allowing you to patch other small niches that Brandishes don't do well on their own. Brandishes also have amazing synergy with some weapons that other weapons simply can not match; Electron Vortex paired with a Voltedge can be a prime example here, and the synergy these two weapons have together is undeniable.

Continuing along with that subject, to use Bopp's words (though they may not intentionally convey this meaning), "Even if you are an expert player, it takes some time to lure the enemies into facing you, and that delay slows your damage output."
This is a significant part of a Brandish's viability, especially when Brandishes can play the patience game just as well as any other weapon. Brandishes can be used at almost any moment freely, so while their damage may be lacking in comparison to a Blitz charge, an Alchemer ricochet or, hell, even a solid Triglav or Sudaruska slam, they still can consistently retain comparable or even higher DPS against anything besides a single target. I'd honestly love to be proven wrong here with some statistics because I honestly can't see very many occasions where a Brandish is seriously outperformed to a point where there's no use in bringing one because you have four other superior choices; from the top of my head, the only things I can think of is using guns for the Tortodrone event and using bombs/guns for Grinchlin Assault.

You mentioned an Undead-themed Compound as an example where a bringing a Brandish isn't the best option; but the loadout you listed is just one of many efficient loadouts that could be used for that Compound-- you could, for example, bring a Vortex bomb along with a Brandish/Troika in order to deal with the minis as well as having more DPS and options than the Arcana, and still devote your third slot to DBB. There may also be times where you couldn't charge a bomb (I'm assuming a mist/vortex bomb here), and a Brandish allows you to basically give yourself space, moreso than an Arcana could. In fact, in the loadout you listed, you could very well add Combuster as your fourth weapon to fill in the one or two niches that those weapons don't cover (although since it's a Compound, those two niches shouldn't exist, but there's always the possibility). Rather than building a loadout that takes on everything you should encounter effectively, there's also the choice of building something around a core then patching up any small issues it has, allowing you to take on everything you could encounter effectively. Here's a quick thought process: Combuster works everywhere but might have problems with minis- add a Mist/Vortex bomb. What about the Greavers that may swarm you? DBB takes care of those. Anything else? Maybe problems with Healers or Howlitzers you can't reach- bring a Poison Gun perhaps, or Maskeraith and a strong Elemental gun, or Drakon and a Venom Veiler. Against anything else you find there, Combuster would perform spectacularly if not beyond expectations, luckily you shouldn't find much else there, but if you do, you have your Combuster with you.

Really all I'm saying is, the pros for a Brandish far outweigh the cons, on a level that very few if any other weapons can possibly hope to match. The fact that they consistently and constantly provide almost the best, effectively makes them the best. In a perfect world where there's no lag and no randomness, this wouldn't be the case, but this isn't a perfect world and the more consistent option in the end is usually the best option. Additionally, their synergy with certain items is outstanding, and giving up two weapon slots for weapons that synergise well usually gives you more options than you lose.
But perhaps I've just lost track of everything.

EDIT (lots and lots):

@Kneeanderthal
"- Combuster. Acheron. Blitz Needle. Chaos set. Try to find another loadout that is better than this one in all situations. (And no, saying this is "boring" is not sufficient, though this set would be boring as f)."

Easy, Black Kat Cowl, Black Kat Raiment, Acheron, Warmaster Rocket Hammer, Barbarous Thorn Blade, Valiance/Iron Slug. Chaos set is uselessly nerfing yourself when Black Kat gives you a universal Attack Up Max as well as MSI Med, having less bad resistances, having resistance/immunity to Freeze, and the more useful Shadow over Elemental defense. Just UV the CTR and you're good. In fact, no need to UV the CTR, they're fast enough on their own. Acheron is on-point, but Warmaster Rocket Hammer could far exceed Combuster in terms of DPS both single-target and against groups while not being limited against Oilers. Barbarous Thorn Blade would make up for Acheron's lack of usefulness (haha, yeah) against enemies resistant to Shadow by giving you a viable AoE alternative while also giving you a relevant damage type. Valiance and Iron Slug are up for debate, they'd be used for long-range, with Valiance being superior in the defensive game and Iron Slug being superior in the offensive game. Alternatively, Volcanic Pepperbox if you still wanted to use an autogun for outrageous damage, but still retaining its usefulness against all enemy types, especially ones you can't reach. Supernova also exists. Acheron could very easily be replaced by Dark Retribution, but for the sake of this I believe Acheron is just useful in more situations, which is the important part here. Likewise, the same goes for Barbarous Thorn Blade and Dark Briar Barrage. You also lack a Sprite, but I'm just going to assume Maskeraith with MSI Med.

@Fehzor
"When the going gets tougher, brandishes start to lose their luster and players wipe"
Very true, but like I mentioned, the only two areas I can think of where this is relevant is Grinchlin Assault (where you are overwhelmed constantly and Brandish falls behind bombs, guns, or even Gran Faust and Warmaster Rocket Hammer, all of which are better there) and the Tortodrones (where Brandishes are literal suicide; and I can't even say it's because swords in general are bad for this mission, because Leviathan Blade is an absolute monster here). I agree here, but realistically, that is just two event missions and are special exceptions; the next-hardest comparable things, arguably Shadow Lairs, are still just fodder for Brandishes.

"When tortodrones first came out, falling back on hail driver was huge for me. Building a loadout around it proved considerably more effective than building a loadout around glacius, or any other brandish for that matter."
Me as well; personally, I started out with Voltedge, saw that failed, swapped to Blitz, saw that it was too unsafe, moved over to Leviathan Blade (which works well! but not well enough), and eventually settled on just switch-shooting Hail Driver and Storm Driver-- and I have to say, it feels great beating Elite Tortodrones and still having my Emergency Revive left, especially when my teammates Spark like five times each. But this relates back to when I said "there's also the choice of building something around a core then patching up any small issues it has, allowing you to take on everything you could encounter effectively". This situation is simply taking a good all-around starting weapon (in this case Hail Driver) and building on it to fill in the gaps (perhaps Flourish for the Fiends and Silkwings, Valiance and now Arcana for its solid relevant damage while staying safe and not having the slow bullet speeds of Pulsars, etc). In 99% of cases, that "all around" weapon might as well be a Brandish, but again, Grinchlin Assault and the Tortodrones are both very obvious glaring exceptions; but also again, these are the only two situations where I can honestly say that "a Brandish is seriously outperformed to a point where there's no use in bringing one because you have four other superior choices", and two very specific situations that are both limited-time events are not enough to show for.

"The synergy with vortexes is good but also more a merit of the vortex than the brandish, as Zeddy pointed out to me once, tons of things have great synergy with vortex bombs, iron slug, dark retribution, polaris, triglav."
Also true, but it's much more noticeable when pairing, say, Electron Vortex, with another Shock weapon-- they just synergise much more effectively than others, and with only four real possible choices to pair Electron Vortex with, Voltedge takes the cake. Pairing it with Voltaic Tempest is counter-productive, pairing it with Storm Driver works but only against part of the group stuck in the Vortex, meaning you're losing out on possible damage. Polaris works but sometimes pushes enemies out and its DPS is good, but nothing special. But in comparison, Voltedge dishes out devastating damage while keeping the enemies in the Vortex like the other three weapons would; it's just the most efficient weapon to pair with EV, though maybe not the best.

Now if only we had a certain Third Troika....

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