I'm totally confused. I never even knew that this was an issue, and I agree with the author that that is a terrible solution. If you really have so much CSS that you can't easily figure out what selectors you have, you should probably be breaking it up into multiple files. It's also helpful to use something like sass for slightly better organized and more concise styling.

I've been guilty of this in the past too, but we really shouldn't be throwing up the modern conventions of source code organization for CSS