It's because they call their children stupid names. It has nothing to do with the coaches. For example:
Ma'a Nonu = Mercury
Rodney So'oialo = Peyton
Clearly the All Blacks are aware of this as there is little web reference to the names of other All Blacks' children. Still, two is enough.
Update: of course, the reason the All Black's did win is because Mercury and Peyton weren't playing. That's what I meant to say. Really.