I have a button that will only my my alts forwards.. So when i run out the gates i will end by pressing that button for a few secs just so they are all standing inside eachother. But normaly with my main kinda far back since they are hardly on exactly the same spot.. this gives them a "new main" to focuse fire on, and yeah you can easily turn you alts if a rogue pop up behind... But, the best way to deal with it as i see it is to drop your fire nova totems (spam the button for like 2-3 secs depends if you are specced in it or not, so that you are sure that they are all droped even if one is stuned for a short time, at the time when you see your totems are going off then do a 4x shock, this will kill or drop the rogue to 10% and have him run off... ignor him. and then start you wally on your primal targets. He will be healing him so its a good time to kill another.

ABout the turning keys.. i use separat keys to turn and not the normal ones. I like that better as can move my alt better with follow on.