Hihi Thanos, this is really Yelta posting from work :P
I agree with everything Thanos says here... And I agreed before I realized who he was.
PL should not be faster XP than getting a good group together to XP. Ideally you should be learning your role in party play. Now I agree, a bad player that was PL is still a bad Player if they level in a group, but I think a good player who leveled in a group is a better player than if they were AFK PL'ed. A good player can be taught at 50 how to do their job and what gear to wear, but if they actually participated in their XP gain they should already know this.
I will be a hypocrite here, I had to level glad to 36 and I admit I got a PL. I had no interest in glad and was told that I was REQUIRED to have sentinel for Ifrit. * But this is an entirely different problem *