The PrintWhatYouLike bookmarklet (http://www.printwhatyoulike.com/bookmarklet) does exactly what you're talking about. You can select the contents of pg's article and the bookmarklet will remove everything else on the page. There are lots of other options to reformat any page to your liking. And everything is undoable.
Yea, there is a trade-off between speed and accuracy. PrintWhatYouLike aims more for accuracy- you can reformat the page exactly as you want, but its more complicated to use and takes a bit longer. Readability is fast, but you have no control over the output.
