Clojurians Log v2

I looked at the code of map, and the last transducer arity

[result input & inputs]

looks like dead code to me, as I've not found a way to call that from a transducer chain. Or could someone please enlighten me on how to use that -- I'd love to have transducers work on multiple inputs (like the normal map) without resorting to some Iterator hacking...

defn map
  "Returns a lazy sequence consisting of the result of applying f to
  the set of first items of each coll, followed by applying f to the
  set of second items in each coll, until any one of the colls is
  exhausted.  Any remaining items in other colls are ignored. Function
  f should accept number-of-colls arguments. Returns a transducer when
  no collection is provided."
  {:added "1.0"
   :static true}
  ([f]
    (fn [rf]
      (fn
        ([] (rf))
        ([result] (rf result))
        ([result input]
           (rf result (f input)))
        ([result input & inputs]
           (rf result (apply f input inputs))))))