Optimal XP for 6+ boxes

[Bollwerk]

How do you explain that you've been at it for 2.5 years, and still have 2 thirds (23 out of 36) of your toons under 58 (16 under 50 even), when people on this same forum show they level groups of 5 to 80 in about 30h played? (like this)

I think he explains it right here...

I don't know whats best for quests as i never do them.