every 100 ms increase in load time of Amazon.com decreased sales by 1%
a change in a 10-result page loading in 0.4 seconds to a 30-result page loading in 0.9 seconds decreased traffic and ad revenues by 20%
http://www.peer1.com/knowledgebase/how-slow-website-impacts-your-visitors-and-sales
86% of responsive sites send about the same hefty payload to small screens as they do to large screens...
... page weight overall is on the rise -- Brad Frost
http://bradfrostweb.com/blog/post/prioritizing-performance-in-responsive-design/
80-90% of the end-user response time is spent on the frontend. -- Steve Souders
http://www.stevesouders.com/blog/2012/02/10/the-performance-golden-rule/
https://developers.google.com/speed/docs/best-practices/rendering
https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Writing_efficient_CSS
http://csswizardry.com/2011/09/writing-efficient-css-selectors/
https://developers.google.com/speed/articles/optimizing-javascript
http://coding.smashingmagazine.com/2012/11/05/writing-fast-memory-efficient-javascript/