Explaining Time Capsule's exclusive wireless backups

From the Apple site:
"Say Time Machine is in the middle of a backup and you want to shut down your Mac or put it to sleep. Who wins? Like you have to ask. Time Machine simply stops the backup process and remembers where it is. It automatically resumes when your Mac is active again."
Jobs seemed to be very proud of the fact that the hard disk in Time Capsule is "server-grade"; and for very good reason after all. In the interest of keeping wireless backups intact and consistent, Apple may have used drives compatible with the "F_FULLSYNC" command. Available mostly on server-grade drives, this command keeps file system changes intact, even over interrupted backups; resuming where it left off.
Time Machine supports the command
defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1,
which could enable backups over general network volumes, albeit with a loss of reliability. Obviously this is not a default Apple-supported feature. However, this command may also allow backups to 3rd-party NAS devices; though officially supported backups would be up to negotiations between Apple and 3rd-party vendors.