Right, but I don't schedule backups except for "now"...
So, if I get what you are saying, I should schedule a backup for, say, 5 min from the relative "now", unmount the drive, then sleep the computer. The scheduler should wake the computer up, run the backup, and then since the drive was unmounted, SuperDuper! will unmount the drive for me, and then I can use the "sleep" option to put the mac back to sleep?
Its not a bad idea, just still a bit onerous. I'll give it a whirl tonight.