Just a minor annoyance when FV is active, you cannot "safe boot". You first have to turn FV off, let it decrypt the drive, then you can safe boot. You can envision some pathologies with miss behaving computers that won't boot to the point you can turn FV off, but those issues are rare. This is the only reason in my book to not use FV on a laptop... although disk intensive video encoding does noticeably slow down.
As far as CCC, if you run the backup defaults, CCC reads the files on your internal drive and stores them decrypted on you backup. If you want your backup encrypted, you need to change the defaults (not that familiar with CCC here, it may have an encrypt function). If you are cloning with CC, the encrypted disc image is cloned, so the backup is also encrypted.
As far as CCC, if you run the backup defaults, CCC reads the files on your internal drive and stores them decrypted on you backup. If you want your backup encrypted, you need to change the defaults (not that familiar with CCC here, it may have an encrypt function). If you are cloning with CC, the encrypted disc image is cloned, so the backup is also encrypted.