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GitHub User: igor-alexandrov
Added a comment with solution on GitHub page https://github.com/ryanb/railscasts/issues/12
If you have really large site (maybe some SaaS system), then you probably like my wiselinks gem.
You may find it similar to PJAX, but it is as easy to use as Turbolinks (I mean, easy to start) and as configurable as PJAX.