[dnanian]

I certainly understand what you're saying.

In general, I strongly encourage people to create a partition, and to NOT mix data and backups: it's just not a good practice.

But, if you want, you can "simulate" the same kind of thing by carefully using a symlink.

Here's how to achieve the same thing:

Create your bootable backup. In the root of the drive, create a folder that you're going to use to store the "temporary" items.

On the original drive, open terminal and create a symlink to that folder, in the same location. In other words, let's assume that your backup drive is called "Backup", and on there you've created a folder in the root called "the-special-folder". So, you'd use the following command:

ln -s /Volumes/Backup/the-special-folder /the-special-folder

When you use Smart Update (or copy different/newer -- DO NOT USE ERASE, THEN COPY in this situation), SuperDuper! knows not to replace a folder with a symlink to itself. So, when you update the backup from the source, it'll see the symlink, recognize that it's pointing to the same folder it's about to replace, and it'll skip it instead.

I hope that makes sense. Give it a try with non-crucial data first, to make sure you've got the hang of it. And -- anyone else reading this thread -- use a partition if you can, and only do this IF YOU MUST.