Need help understanding BiS(best in slot)

[Sapphic]

Basically, the starting point is to cap accuracy.

If you really want to maximise BiS.

Using FCoB as an example. Each turn has a different accuracy cap and thus BiS would be having different gear layouts for each turn, as obviously you don't need turn 13 accuracy for turn 10.

Also with 3.0 and the raised stats, stat weights may change. As for example, if what I've read will be implemented in regards to SMN and Spell Speed. Weight on that stat will increase.