This might work for documents but a difficulty I see is how you would handle system files. See, with documents it's fine to always return a collection of files,

This might work for documents but a difficulty I see is how you would handle system files. See, with documents it's fine to always return a collection of files, but for a system file say /etc/passwd, you want to make sure you get exactly (status quo guarantees at most which is almost but not quite as good) one file.