Agile Web Development with Rails 4: Refreshing pages following editing of files

Page 28 box suggests that there is no need to restart the server during development in order to see changes made to various files in the scheme.
My experience is that it is necessary to restart. It may be that I’m doing something wrong.
Mt dev setup is a vagrant virtual machine running under virtualbox inside a linux mint host. I am sharing the workspace from my host machine into the vagrant machine via the Vagrantfile.
It isn’t much of a problem at his early stage, but maybe an issue for the later more complex examples in the book.