So yes it does work but now I'd be concerned about brittleness based on the comment. I can't think of why it should affect Nova material more than say any other plastic and I haven't had to do it again. Normal scrubbing with a bottle brush using water has been enough.
My problem stemmed from leaving fix in the slot for months without using or draining. I suspect that if the processor is used often then the black coating doesn't take hold because the old fix is dumped often enough and a quick "scoosh"( liquid sloshed around the slot quickly in a jet-like form for non Scottish readers with water is enough.
I don't suppose strong bleach does any material much good if used very often.