I'm asking for my father...I'd like confirmation that this will work. He might try out Yosemite on his MacBookPro (per advice from the Apple Store), but he's very concerned about the ton of negative comments on the Apple page. He's currently on Mountain Lion. He has extensive backups of it (bootable). He likes using it. The QUESTION IS IF he upgrades to Yosemite, and doesn't like it. CAN he use the backup to clone back the MacBook to where it is now?