I've successfully completed Turn 4 multiple times, but as I've moved to different groups, it seems like certain strategies won't work depending on the group composition and gear level.
It seems like the bread and butter method of dealing with T4 is:
1. Kill the second set of bugs so the Dreadnaught doesn't get any stacks
2. Kill the Knight and Soldier who drop down with the second Dreadnaught
3. Hurt the Dreadnaught
4. After the final adds spawn, stop attacking the second Dreadnaught and kill the Rook that appears with the final set of adds
5. Finish off the initial Dreadnaught
6. Kill all enemies besides the final Dreadnaught
7. Kill the final Dreadnaught while healing through enrage timer
I've successfully used this strategy. However, it seems like there are some issues with this method: You can't always get a group that can kill all the bugs, the bugs in the final phase can accidentally be given to the first Dreadnaught, you have to deal with the enrage timer with this method, the AoE phase is a large TP/MP/non-GCD drain, and it's a large strain on the MT. In no way are these problems definitive or can't be avoided, but those are problems I've seen.
I've successfully used a variation of the strategy, which has its ups but definite downs.
1. When the second set of bugs spawn, only kill the Rooks, and everyone else does nothing to conserve all resources.
2. Dreadnaught spawns with full stacks, Hallowed Ground is used by MT, OT kites adds near entrance, Dreadnaught is burned down first and foremost.
3. Shortly after, final adds spawn, OT uses Hallowed Ground, everyone kills Rook.
4. Adds are burned down as quickly as possible, in the order they dropped.
5. Kill final Dreadnaught
This strategy seems strange, but its benefits over the more standard strategy are less of an AoE DPS requirement, in general a low gear requirement on all members except the OT kiting the adds, the final bugs are much less of a liability since the only Dreadnaught to eat them will be at full health, and you avoid the enrage timer for some reason using this method. The drawback to this method is placing the entire raid's survival on the OT, who needs to be competitively geared and work hard to hold threat from healers with all adds and survive. This strategy seems more all-in, which leads me to love it when it works but want to abandon it quickly if it doesn't.
I've toyed with other variations, such as instead of the kill order being Knight/Soldier > Rook > 2nd Dreadnaught > Knight/Soldier > 3rd Dreadnaught, it being Knight OR Soldier > Dreadnaught > Rook > 3 Adds left > 3rd Dreadnaught, which spreads the strain to both MT and OT (whereas strategy 1 has most strain on the MT, strategy 2 an extremely large strain on the OT).
Anyway, as this turn is effectively on farm, what do you feel is the best way to deal with it? Assume a party of BLM/SMN/BRD/MNK rather than something like BLM/BLM/BRD/BRD or something.