(I keep thinking -- what has this got to do with North American Network Ops?)

  instead we treat it as (leaving out the '<' '>' stuff out of laziness):


  and look up like this:

    ask a ROOT nameserver for M NSes
    ask a M nameserver for O NSes
    ask a <w> nameserver for appropriate info

That's an implementation detail; the protocol won't (I mean, wouldn't :-))
have to change at all to support this.