Quote Originally Posted by david357 View Post
Now another idea comes to my mind : I could have team 1 boosted by ACC2 so that there would be only 4 people in the dungeon, does anyone know how it would impact my xp/mob ? I heard that adding low-lvl characters have an impact on average lvl so that it becomes more interesting to boost 4 people instead of 2 for example, is this right ?
Why only 4? You have the two that were recruited, the two that did the recruiting, and a high level booster.

There is a formula for calculating how much exp you get, its in one of the forum posts if you feel like searching for it. Your toons do get less exp per kill because of the higher level toon in the group, and as your toons level up you get more exp instead of less from killing the same level mob.