Caerdwyn writes "Cotendo, which is a content distribution network, has taken to altering HTML as it passes through their CDN to optimize web pages for faster rendering. This is essentially a repackaging of the Apache mod mod_pagespeed (from Google), with the critical difference being that the rewriting of HTML occurs inline rather than at the web server. We all know that well-written HTML can result in much better rendering of whatever your content is; the questions are 'Will this automatic rewriting cause other problems, i.e. browser quirks?' and 'Assuming that only the web pages of Cotendo's customers are altered, are there nonetheless potential legal troubles with someone rewriting HTML before delivery to a browser?'"