The advantage of having a bare bones bootable copy of just the OS is that if you feel something has gone wrong with the OS and it has affected both the installed OS and the CCC made from it, is that you can start with a fresh known-good OS and then migrate your data to it. I used to do the same thing, but now I alternate between SuperDuper! and CCC and clone every few days or so. I believe that if something goes wrong with the OS, I should know it within a week and can use one of the backups, so I no longer keep a bare bones OS copy. I also keep another copy on another HD and update that every 2 weeks to a month. I also have Time Machine running on a separate HD. As you can see, I believe in safe-guarding my data (I should also keep on off-site copy, but just haven't gotten around to it). Thus, I think the more backups, and on different HDDs, the better. So if you feel the bare bones OS might serve your needs in the future, I say go for it. ;-)