Power-leveling is absolutely BROKEN

[Vahzl]

Ignoring the fact that XI went downhill since level sync, I want to point out a flaw in your logic.

Sure, there were a few ways to increase xp/hr on SOME party configurations. I won't even call it an exploit for the sake of argument. However, in this situation, you can take ANY level 50 player and powerlevel a full group of ANY class. It is completely and utterly broken, there's simply no arguing that.

You could replace up to 3 members at a time with any class, and still have the same effect.