.... I may be totally off base about this, but I guess the idea is that the enc file could be corrupted. If so, you might not discover this until a day (or 3,5, or 10) later. In that case, you would want to go back to the last file that was still healthy. I know...this is all pretty unlikely, but as we all know, unlikely scenarios is what complex backup regimens are for.
It is unlikely, but I have run into it. I did blink a few times when the restored failed ~85% in. I grabbed another .enc, and it worked, but that failed restore message is not one that anyone wants to see.
