This term is never defined or used anywhere. Let's talk about the layout
file instead.

Avoid the "easiest", "inadvertently" expressions.

EXCLUDE_RESTORE and EXCLUDE_BACKUP are irrelevant for layout file and
disk layout recreation. They merely influence file backup or restore
(for supported backup methods). This guide is about the recreation of
the disk layout. Therefore, omit the variables from here. They are not
used in the doc anywhere anyway after showing a copy of their
description originating from default.conf. So, why to show it at all?

I believe that "This behavior is controlled by the
+AUTOEXCLUDE_DISKS=y+ parameter" must refer to the exclusion of the
unused backup disk. At the current location (disk layout when the backup
disk is NOT unused anymore) it does not make sense.

Move the whole part about autoexcludes just after the section where it
is mentioned that a disk was automatically excluded.

Show only the parts that have changed after changing something.

4d6fac7 changed the formatting of
commented entries in layout:

"Change commenting in layout file to have no space after the #."

Adapt the examples that had been generated before the change to match.

Instead of copying a snippet of default.conf, describe in prose what the
variable does and what is the syntax.

Instead of referring to what seems prudent, describe the assumptions
beyond the example explicitly. This way, the reader can understand what
we want to achieve, regardless what is their opinion on what is prudent
and what is not.

Also, describe briefly the relation between layout configuration and
backup exclusion.