Originally Posted by
Ayirez
He did write that it'd be an option, so that you can chain kill mobs with friends new to the mode, not that it'd be enforced. That would be silly. I'm a fellow Lv.20 and while riding the train is by far the most effective means, doing so from levels 1 to 5 don't yield that much reward compared to chaining mobs, they should go to low level NM's sure but chaining would be better.
All in all the guy was just saying he wants to play with his friends and that lower levels get left behind which is already coming to be a reality, people selectively vet the people they're recruiting so that they're high levels.