Not the south has to click before the north. Has to solveeach level before the north. Let the south solve completely the 1st ring and be the initiators of the fight. Then the north...etc. You dont need to do any kind of a countdown, even on hard/nightmare the mobs are easy takedowns, so when the south has solved the first ring let the north do it. Once north does first ring have south solve 2nd ring, and so on.
Also I would recommend splitting into 2 8 mans. Alot less buggy.
We'll give that a try. Also we have no intentions of running 16 man's for now, there's just no point.