A bit late to the game, but I was honored to write an article for this years Performance Calendar earlier this month. The article was a gentle introduction to using Phing to automating performance tasks. Fitting right in with the “Performance Toolbelt” posts I started adding to the site this year, it introduces yet another freely available tool that can greatly simplify the process of optimizing performance.
Be sure to check it out. While you’re at it, have a look through the rest of the articles. There’s some great stuff in there about mobile performance, new tools, the state of WPO in general, response and request headers, etc. Definitely worth browsing through.