I wish that WiS took more/any steps to prevent known problem owners from moving from world to world under aliases, because most of the quality long-term owners I've found for the world I commish have been rookies. Obviously, some n00bs find the game isn't for them and move on, but it's certainly not a safe bet that those experienced owners who can demonstrate a track record will keep their fourth or fifth team in my league for 10 seasons or more. A lot of times they're just shopping around until they find a ringer of a team, whereas rookies grow more attached to their first team if the world is a good, one which I like to think mine is.
But I'm less and less willing to take chances on apparent n00bs because I have no idea whether they're someone who has intentionally trashed a team for whatever crazy reasons people do that. Not sure what WiS can do to help, but right now they're not doing anything.