The label of "immitator" is an unfortunate choice. It can have something of a negative connotation. We tend to prefer "originals" to "copies". With koi, all are unique. Nobody is going to produce a copy of the Kato Showa... wish they could. At the same time, even the "innovator" is using the genes of the innovators who came before.
I know what JR meant, but I think he was being purposefully simplistic to make his point. I prefer to think of that one style is focused on refining what came before; and the other is focused on re-arranging what came before.