I haven't been able to start raiding yet but I feel like, logically speaking, 16 people would increase the chance for user error by 100% Even if the content is geared correctly the more people you add to a situation, after a reasonable amount of course, the harder it's going to be, skill wise and organizationally. If you have 16 people that all work well together than you won't see much of a difference, if any. I know if I were given the option though I would always compete for the best possible the smallest possible group. It's just easier to keep track of what everyone is doing.