I kinda find that killing in monster LV50 dungeons are a bit of waste since they don't yield EXP.
So what I was thinking if they dropped tomes, like only 1 per kill so it doesn't go over the top. Because I also noticed when I'm in dungeons people skipping some mobs just to rush to the boss since you don't get anything for killing them. So what do you think? Kill 1 mob and get a Tome or kill a group of Mobs and get Tomes?