It was 2 people 1and they didn't know each other, why would a new level 12 player even expect a level 70 in a L12 dungeon (yeah I forgot to warn them). They wanted to go out and do things on their own to learn the game maybe meet others their level. You say they can group with friends you can say the same for a L70…
The solution does not seem to difficult maybe someone else proposed it I've not read every page of this thread, here's a few options. Option 1) Group toons in leveling dungeons by level, 10 - 30, 30 - 60, 61 - 70 (just an example). Option 2) If you get to far ahead of your party (system tracks distance) you lose AD for…