Site compression through something like google-weblight has pros and cons. On one hand it loads pages 4 times faster, on the other it changes the look of the site, thus altering the UX.
Also, my assumption is that users care about site compression when browsing on telecom provided data, but not so much over WiFi.
What should be the middle ground?
We heard at Google I/O about Google's plans to help improve the experience of users on slow connections, especially in parts of the world where even 3G speeds are few and far between.
Google's estimates have you loading the page 4x as fast compared to the unaltered version when on a slow connection, with 80% less data. They claim, appealing to webmasters, that this results in 50% more pageviews due to the better experience and lower wait.
for more study:
http://www.bruceclay.com/blog/mobile-seo-responsive-design-image-optimization
