I think the staff should ban people for good if they have been caught teaming once or twice.To everyone saying you can't do anything about teamers except report them: No.
We CAN do something about teamers, and that is making the ban longer and punishing them harder. This will work, for the same reason people are less likely to drive too fast if the fine for it is a lot of money.
HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA. Heck no.
There`s no point of increasing the ban length, since they won`t learn to stop teaming.
I even caught a diamond rank teaming with 2 stone ranks and another diamond rank once. (I won the fight :P)