Agile Web Development with Rails 6: Usage of `@page_title`on page 108 f

Hi,

the code on page 108 (and the explanation on the following page) mention the instance variable @page_title, which doesn’t get used elsewhere in the book (or the zip file with the code from the book).

I wonder why that is? Did I miss something or has my search-fu failed me?
It seems a bit untypical for a pragprog book to introduce something, and then not use it.

I really like the book BTW! It’s nice to read and fun to follow along.

Cheers
Stephan