Mostly opinions without data, as usual. Why can't we as a community switch to a more serious scientific/engineeristic approach, at least in those areas where it

Mostly opinions without data, as usual. Why can't we as a community switch to a more serious scientific/engineeristic approach, at least in those areas where it is easy to do so? Why should I trust this blog post on the "Caching" point, for example? It's got no data and no references. "What are the chances that your user has visited a site which uses the exact same CDN as your site?" ... hey, you can measure that.