Hopefully my wonderful colleague Peter won't mind my
amplifying that a tad.
Maybe it will help to think of things this way. If you used a
Find and Replace tool to accomplish this, you would have to launch
it separately and let it work its way through all the topics if you
wanted a different build. Then you would compile or generate your
With Variables, you could configure several layouts to do
this for you. As Peter indicated, there is less of a chance of
error. But moreover, it would also save you from having to remember
to perform the Find and Replace operation. You would declare the
variable value only once in the layout properties. Then all you
would need to do is compile or generate the desired layout to get
the customized version.