I don't know if people actually use this formation... Don't most prefer 1 FBB 2 BB 1 CVL 2 CV...?
Zero chance of dead-end, 6 potential Night Battlers at the boss node compared to 3, and the "sub-killer" node can be curbstomped by the BBs and Node Support.
I don't use it as my main formation because my stronger/luckier SSVs are kinda low leveled (50-60ish, while I-168 is 80ish) but I can see the potential behind it
I used to use this comp until I stopped due to the annoyance of almost constantly having to retreat and resparkle the subs made it a terror and the fact that the chance of killing the boss was fairly low.
I'm going to give 3FBB 3CV another try once Italia and Roma are 90+.