Agreed, it wasn't meant to be a comprehensive guide to speed, just tackling the quickest one. You can run these compressors in a matter of minutes whereas CDNs

Agreed, it wasn't meant to be a comprehensive guide to speed, just tackling the quickest one. You can run these compressors in a matter of minutes whereas CDNs can take a few hours to implement, and generally can't be run by everyone (whereas ImageOptim can be run by basically anyone). Perhaps some day I'll create a mega checklist of all things to consider to speed up a site :)