Primary cause of T5 Divebomb failures

[Sove92]

It should also be noted that T5 is the only instance so far where the divebomb mechanic works backward: Divebombs come from where the marker APPEARS, not where it disappears.

T13 Divebomb works the same way, the difference is T5 DB has a cast time of 1s, the ones in T13 have have 5.

[Lemuria]

Because that's not true of every battle up to T5. Of note, the two cyclops enemies available at launch have no AOE markers at all.

True, but that doesn't mean the attack isn't telegraphed. You can see exactly when they're powering up, and you instinctively know to back off. You don't need the AoE marker because you know the AoE is centered on the cyclops.

With the divebombs, the marker above a player tells you nothing, merely who it's targeting. You don't know which direction it's coming from, nor the resulting size of the attack. For all the player knows, it's as wide as a house and swoops in from all angles.

You would think that the developers would've patched it by now if it was an exploit and not intended.

Not really. Ninja tanking using Utsusemi was considered an 'exploit' in the early days of Final Fantasy XI. It was never 'patched' because everyone was so used to doing it. If they actually patched this exploit so that people couldn't abuse the pit they would have literally every single coil player screaming at them. SE aren't stupid, they know when not to 'fix' something just as much as when to.

[Sove92]

With the divebombs, the marker above a player tells you nothing, merely who it's targeting. You don't know which direction it's coming from, nor the resulting size of the attack. For all the player knows, it's as wide as a house and swoops in from all angles.

You can actually see where the dive is coming from, and Twintania will always dive from the same location on that particular spot. So if you stand in center of the arena and get targeted, Twintania will dive from a predetermined location at you, and that's where she always dives from if a party member in the middle is targeted. There isn't really anything strange about the mechanic. If it was as random as you are claiming, the ditch method wouldn't work. The ditch is popular because it causes about 75% of the dive's width to go outside the arena, that way you need to move less, giving you enough time to get back in the original position.

[Viridiana]

True, but that doesn't mean the attack isn't telegraphed. You can see exactly when they're powering up, and you instinctively know to back off. You don't need the AoE marker because you know the AoE is centered on the cyclops.

But you have no idea how far to back off. I pretty much never get hit by it and even I don't know how far you actually need to be to avoid it. Partially because the easiest way to do the fight is to never leave melee range. >_>

Edit: As a second example, there's no AOE indicator on any of the Chimera voices, either.

[Dement]

You can actually see where the dive is coming from, and Twintania will always dive from the same location on that particular spot. So if you stand in center of the arena and get targeted, Twintania will dive from a predetermined location at you, and that's where she always dives from if a party member in the middle is targeted. There isn't really anything strange about the mechanic. If it was as random as you are claiming, the ditch method wouldn't work. The ditch is popular because it causes about 75% of the dive's width to go outside the arena, that way you need to move less, giving you enough time to get back in the original position.

I would add that the ditch is also the go to area because the DPS check on the snakes used to be very tightly tuned before echo and overgear to the point of simply killing the snakes in time was almost as difficult as dodging the divebombs themselves. The Pit is where the first snakes pop so that you're already standing there and can jump on them as quickly as possible.

The Pit isn't an exploit, it's just the most efficient way of doing it. Otherwise, everyone stacking in the center for T13 divebombs so that Bahamut and Twin always pass through the center is just as much of an exploit.