The problem lies in the fact that lv 50s prioritize themselves and give no concern to anyone possibly leveling still. They're not there to help, they're there for tomes, or whatever drop they need for THEIR concerns. Anything else is irrelevant. Thus you get healers tanking, tanks overpulling and overtasking healers who are leveling, overzealous DPS, etc. . . The list goes on.

My motivation to run dungeons, or even get tomes from roulettes has hit an all time low because of this, and that's terrible. Those Solo/GC Party dungeons really need to be a thing soon.