How do you measure page load speed?
I am trying to quantify "site slowness". In the olden days you just made sure that your HTML was lightweight, images optimized and servers not overloaded. In high end sites built on top of modern content management systems there are a lot more variables: third party advertising, trackers and various other callouts, the performance of CDN (interestingly enough sometimes content delivery networks make things worse), javascript execution, css overload, as well as all kinds of server side issues like long queries.
The obvious answer is for every developer to clear the cache and continuously look at the "net" section of the Firebug plugin. What other ways to measure "site dragging ass" have you used?
