As stated above, it is technically allowed, although it's sneaky and as people have said, won't win you many friends. Ultimately it's the other players decisions' to /kill and let the other person win, and we aren't going to take action on players if they want to let someone else win.
The instance where it is not allowed is connecting with alternate accounts (of the same person) at the same time in order to /kill and boost wins.
Thread locked.