I was evidently unclear. When I say "billiard-ball determinism" I mean the caricature of determinism many people think of, the one in which free will is impossible because everything is "merely" physical. If no decision were "free," any evaluative statement is pointless. It would be like water deciding whether or not it is "right" to flow downhill - it doesn't matter what it thinks, it's going to happen.

I agree that this is not an accurate rendition of reality. I just find it amusing that people who do think it's an accurate rendition of reality still find the free-will debate relevant. If there is no free will in that sense, there is no point whatsoever to debating it, nor to discussing morality, because it's a done deal.