I broke up parts of the rationale page and combined them into other pages instead of adding them on the get started page
per Andre's requests:
Grouping - The section about "groups" should be merged with the page that is linked as "Grouping" in the sidebar.
Set Up - The section about "set up your application to use bundler" should be merged with the Bundler.setup page.
Sharing - The "check your code into version control" and "share your application with other developers" should be put into a new page named "Sharing" and linked in the sidebar Usage section.
Updating Gem - The "updating a dependency" and "updating a gem without modifying the gemfile" sections should be put into a new page named "Updating gems" and linked in the sidebar in the Usage section.
Deploying - The "deploying your application" section should be merged with the existing "deploying" page that is linked in the sidebar.