Players connot join the party while you are engaged in combat

[Kam]

The biggest issue with it is people claiming open world content that they aren't ready to fight/kill and just holding it until they can get enough people to fight it.

Another issue would be people dropping just so they could switch jobs mid-fight and killing something by abusing mechanics while they wouldn't be able to otherwise.

Thats what rage timers are for, and you cant /logoff or leave party while engaged in this game.