It would be cool to see this feature return!

[Felis]

Sadly, this feature was deemed too difficult for modern MMO players to comprehend, and was thus removed with the transition from v1 to v2. Interesting as it was, I doubt we'll ever see it again. The same holds true with Battle Regimens, which were incredibly powerful when executed by a team with coordination.

It was less about difficulty, but that specific jobs were favorised against specific enemies.
Chimera in CC? Change to Monk to destroy his tail if you are not the healer or tank
Want to farm Aldgoat horns? You need 1 of 4 specific skills to break the horn first to get a chance for the drop.

Battle Regiment was only usefull if everybody in the party knew how it works.
https://www.youtube.com/watch?v=L23sldpDSmA