Right. And to me, this is the interesting part. There's always been that size/speed tradeoff ... by putting huge amounts of memory bandwidth on "less" main RAM,

Right. And to me, this is the interesting part. There's always been that size/speed tradeoff ... by putting huge amounts of memory bandwidth on "less" main RAM, it becomes almost half-ram-half-cache; and by making the SSD fast it becomes more like massive big half-hd-half-cache. It does wear them out, however.