If you steal one worker usually a busy worker next to it won't react. Can't tell you why, but that's how I usually end up with multiple worker steals. Of course, excess defending units can react, so even if captured that second worker can get recaptured next turn.
I'm not opposed to worker stealing, just think it has a better risk/return at the very start - we could have grown on warriors instead of worker first. I also prefer to grow the city a bit over grabbing a size 1 settler, because as BiC pointed out if we lose that spot we don't have a timely backup (other spots require TW or fishing). The thing is we've already picked AH first, and that mostly made sense to me assuming size 1 settler.