of the time, so having minification is good since we still get some reduction even when the browser does not support gzip. And when it does, we end up with less than 1/5 the size of the original file.
How does that compare to total bytes per page impression? My guess would be: negligable. One thumbnail on the page and the JS savings become marginal in comparison. Plus the JS should be cached by the brpwser (as opposed to new thmbnails on different pages) Bottom line, minification makes JS debugging a pain in the a.. for a comparatively low benefit.