When I'm looking for spammers, the name is an obvious clue. The have some standard behavior, such as listing random words in the Lavishsoft Key input field, listing 123456 in the Multicaster field, actually putting something in the homepage field {you'd be surprised how few legit users list a homepage in their profile!}, putting "man" or their own username in the Biography field.

Once I ban someone for something like that, I would go look for other users listed on the same IP, which is what the new measure is doing automagically.