Riot-
Are you saying that your guild leader can go through a 100% hard level and kill all the mobs by himself? If so, I smell bulls**t.
Even if it were possible (which it's not) he'd level 3 times over the course of the mission and would be level 125+ in a couple days.
Maybe you meant that he can run like hell though a 100% hard mission and get the item & reward? Anyone can do that with a little luck.