I was attempting to optimize my scene and it seems Arnold still exports hidden objects when rendering to picture viewer BUT not when exporting ass files.
Picture viewer Render with hidden geo:
00:00:15 17912MB | scene creation time 0:11.94 machine utilization (0.14%) 00:00:15 17912MB | plugin loading 0:00.49 00:00:15 17912MB | unaccounted 0:11.44
Picture viewer Render with no geo:
00:00:04 17868MB | scene creation time 0:00.58 machine utilization (1.21%) 00:00:04 17868MB | plugin loading 0:00.48 00:00:04 17868MB | unaccounted 0:00.09
Is this a limitation of cinema or is this something that could be change to behave in a similar way that .ass files exports handle hidden objects.
When I export .ass files from C4D it does not behave in the same way. Hidden geo will not be exported. This only happens when rendering straight to the picture viewer.
Related post about export .ass files in Maya with hidden objects.