Your strategy of using two JS scripts per view, one site-wide and one page-specific is interesting. I wonder how to test the performance to really determine the value. Maybe look at time-to-render?
Then I have an application level CSS&JS that has everything generic in it. This is for a reasonably big app, so the overhead of having a single CSS/JS isn't insignificant - particularly when supporting mobile devices.
The other useful thing is a I as a dasherized version of the controller name and action to the body tag - as an id and a class respectively. So the body tag is something like
<body id='my-controller' class='show'>
These constructs are to be used sparingly -- you don't want to mash everything together too much -- but they're very handy when used right.
One other optimization you may want to talk about in your next article is to use a gem like the asset_sync gem to upload your assets to S3 or CloudFront (or similar) at compile time.
On these occassions the hit to download JQuery (or something big like JQueryUI) is zero.
This is more a consideration for a landing page than a heavy-use application though.