You dont need mega players to take down duke. I remember i was in a group of about 20 who beat him for the mission and i was 1 of the strongest in the group, i probably only had about 2 billion stats back then and we beat the duke in the first attack.
I know that, but if you look in op profile you can see that he (same as me) will be in hosp after first hit and managing 20 players to attack same time is pretty hard, it is much more easier hire BB.
Weekend is the best time to set up a attack. I remember mine being on a sunday evening. It was on one of those attack duke threads where we set it up so there was nothing too arduous involved.