An excellent question.
I think it makes sense, at this point, to go over our weapon attack options, so let's talk about Final Fantasy V's abilities that modify weapon attacks (aka why I'm not enthusiastic about Dragoon in this system). We can separate them into rough categories based on how they adjust your overall baseline from just hitting the "Attack" command with no ability equipped.
50% damage output:
Dragoon's !Jump (without a spear) - If your dragoon doesn't have a spear, something's gone very wrong. They need a weapon with double damage on !Jump to compensate for only attacking every other turn. Deals full damage from the back row.
100% damage output:
Monk's !Focus, Dragoon's !Jump (with a spear) - With both of these, you attack every other turn for double damage, meaning your effective damage output isn't increased or decreased. The Dragoon gets to spend that turn off the field but that only rarely matters. !Jump deals full damage from the back row.
Hunter's !Aim - Always hits, so it can be used for evasive enemies, but you probably have better options. Particularly if you've unlocked Rapidfire.
Dancer's !Dance (without Sword Dance equipment) - You have a 25% chance of Sword Dance for 4x damage, so overall there's no damage increase from that, but the other abilities do include a charm effect, HP drain, or MP drain as your other options, so that's your side-benefit, and a minor damage increase that isn't enough to move !Dance from this category. Deals full damage from the back row.
150% damage output:
Berserker's Berserk - This is a damage increase, but it comes at the cost of not getting to play the game with that character. I'm not a fan.
200% damage output:
Knight's Double Grip, Ninja's Dual Wield - Both of these sacrifice a shield (which can matter—shields are good in FFV) to double damage output. However, there's a key difference for building a strong physical combo attacker: Dual Wield is an inherent ability, meaning Freelancer gets it if Ninja is mastered, whereas Double Grip costs an ability slot to be equipped.
Dancer's !Dance (with Sword Dance equipment) - You're basically sacrificing some turn-by-turn consistency to deal quad damage half the time. The other half the time you drain some MP or HP from the enemy. Deals full damage from the back row.
Hunter !Rapidfire - Hits 4 times for half damage each, ignoring defense and always hitting. In this case instead of sacrificing turn consistency, you're sacrificing targeting, in order to do double damage overall.
Special damage output:
Mystic Knight's !Spellblade - The overall damage increase of this depends on two things: whether they have an elemental weakness (you don't get the damage multiplier without it on elemental spells, though non-elemental spells can give you a damage increase) and how long the battle goes (there's a setup turn, but unlike !Focus or !Jump you don't have to spend every other turn on it). When these align in your favor (viz. in many tough fights) it's the best weapon damage ability in the game, giving you 2x, 3x, or 4x damage with elemental spells.
So, looking at the pieces we've assembled, several combinations become available, and they can often combine in multiplicative ways. If you put Dual Wield on a Dancer, for example, your !Dance will hit with both weapons, for an overall damage output of 400% compared to just hitting with a single weapon. Once you have the gear for it, Dancer is a genuinely good physical attacker.
You can probably now see why the Spellblade + Dual Wield + Rapidfire Freelancer combo exists. It's taking the highest available damage multipliers that you can use at the same time and smashing them together. !Dance can substitute in for !Rapidfire, but while the damage is theoretically equivalent in most cases, Sword Dance's quad damage hit can run into the damage cap more easily than Rapidfire's half damage multiple hits.
Which might be a pro, if you want to see the number 9999 pop up on your screen.
no bulli!
