That's certainly interesting but it's usefulness is unfortunately limited if its only saving system memory which is pretty much always in surplus on a half decent gaming PC. If it were saving VRAM that would be pretty significant.
That said, the fact that it's saving system RAM rather than VRAM is quite revealing wrt how this game at least is using the PCs memory hierarchy for streaming. It seems system RAM does indeed act as a cache between VRAM and storage and will be utilised to mitigate slower storage speeds.
