Please reduce the CD and duration of Arm's Length.

[DRKoftheAzure]

because I wan't classes to feel different insteaf of just having every class capable of doing everything.

So... bring back cross-class then...?

[Rasikko]

I think the OP is only referring to the anti-knockback aspect, and not the Slow affect.

[VenKitsune]

Why would it need a cooldown reduction?

the shadowbringer fights are DESIGNED with the cooldown in mind - Do you know what would happen if they reduced the cooldown? They'd increase the ammount of knockback skills so the only thing that would change is that it'd be pressed more which would be annoying.
Pre-shadowbringers only a few jobs had a knockback immunity - Namely PLD and WAR and maybe a few others i cant think of right now. This means that knockback prevention isn't needed for pre-5.0 fights, and the post 5.0 fights are designed with that availability of it in mind which means that on fights like E4S you actually have to use it tactically in P1 to make sure its up for the first blue in P2, for example, or just do the mechanic correctly.

It's also worth noting that if they reduced the cooldown then they'd also need to reduce the cooldown of surecast - Both surecast and arms length have aditional abilities tied to them in the form of guaranteed interupt-less casts and a slow-on-strike. If the duration was nerfed to 3-4 seconds as you say...That'd mean that Surecast wouldn't even last a single spell cast in the case of some jobs like blackmage's flare.

Useless thread is useless.

[Rongway]

Why would it need a cooldown reduction?

the shadowbringer fights are DESIGNED with the cooldown in mind - Do you know what would happen if they reduced the cooldown? They'd increase the ammount of knockback skills so the only thing that would change is that it'd be pressed more which would be annoying.

This. Broadly, knockbacks in ShB have been timed so that immunity can be used on alternating occurrences, forcing you to execute the mechanic as intended exactly half of the time. This is clearly a deliberate design choice. They wouldn't decrease the recast timers by half without also doubling the frequency of knockbacks in future content, so that knockback blockers can still only be used half the time.

Pre-shadowbringers only a few jobs had a knockback immunity - Namely PLD and WAR and maybe a few others i cant think of right now. This means that knockback prevention isn't needed for pre-5.0 fights.

In Stormblood, everyone had a knockback blocker except DRK MCH BRD. All mages had Surecast, all melee DDs Arm's Length, PLD Tempered Will, and WAR Holmgang.

Surecast originally was fairly pointless, as the Stormblood launch incarnation of Surecast kept the ARR/HW behavior of consuming the buff on start of spell cast, which meant it wouldn't block knockback unless you stopped casting for 3-5 seconds after activating it. This meant that using it was the same as or worse than just repositioning for the knockback and getting knocked back and then resuming your rotation. But once it was adjusted so as not to consume the buff, Surecast became severely OP--it was up for almost every knockback mechanic ever.

The knockback blockers available to Disciples of War were on longer timers and not available for every mechanic, but enough for about half of them? I don't DoW much, so not certain, but that's what it looked like when observing melee DDs in the Omegascapes.