The number one reason why i will start single targeting on a pack, is tanks who are moving way too much. I place my bishop turret right in the middle of the mobs, they all go out of range of it, and i just wasted a 10 seconds cd. It is even way more frutrating trying to blow up the turret at the right time. And since grenado shot was deleted, i dont even talk of trying to corrrectly aim the spread shot's cone when mobs are running everywhere. And that's with stacked mobs, some tanks don't even try to do proper packs to optimize aoes damages (one of the best examples being the halgais in Uznai's first room).

So when most of my aoes are hitting almost nothing, i switch back to single targeting to do more damage. I dont think it would please me to be kicked for that when in fact, it is the tank's fault to not be able to stay still a while and hit a defense cd.