This is extremely week argument for CSS Lint. CSS is not the starting point (unless you are talking about CSS sprites) for the performance optimization, and, frankly, it may never be a point. On a normal page it would be hard even measure difference between performance of class vs. descendent selector and littering your markup with classes may offset any benefits by simply getting bigger document which takes longer to parse.

And tell me, how making id selector (the fastest) persona non grata helps performance?

"Rebutting" a single point (which was not even a point, just a note, based on how do you "fee" about the author, does not rebut anything.

I am a programmer and I tell you: CSS Lint won't make your pages faster. It may make the slower, but that does not matter, cause nobody will notice it either way.