Re:Classes? Where We’re Going, We Don’t Need Classes (CSS)
by lazerwalker on Tuesday June 19, 2012 @11:00AM
(#4132137)
While that Mozilla page is completely accurate, it's very rare that your CSS is your site's performance bottleneck. The vast majority of the time you're better off making your structural CSS choices based on developer maintainability, not prematurely optimizing rendering performance.
And really it would be better to avoid references to linguistics when talking about a markup language, especially references from early structuralism which, basically, has failed.