But if you want the ability to do things like this, why not just use a preprocessor? This is a step forward in the CSS spec, but until it offers more of what SASS/LESS etc. do, I certainly won't be going "Look at @apply! No more SASS for me!"

If you were starting the development of CSS-Tricks today, would you still use WordPress? If not, would you build it from scratch or use another existing CMS (or a hybrid)?