Nothing annoys my writer wife more than people not using "less" and "fewer" correctly. "If only my life was so problem-free" you may say, but no, it's really starting to annoy me too. And, I'm not just meaning it annoys me when the missus yells at a reporter on the Today programme in the morning from under the duvet.
Don't get the idea that I'm one of those pedants who carries a red marker pen for adding missing apostrophes to Tube posters, but the misuse of "less" and "fewer" seems to be getting worse. "What do they teach our children in schools these days", I hear myself say in my father's voice. It is a big deal. It may not cause confusion as to some the words are interchangeable, but when you do know the difference it jars terribly and the reader's focus is lost.
To clarify: Use "fewer" to describe countable things. Use "less" to describe uncountable quantities.
Last week I nearly fell onto the tracks when I saw this poster on London Underground. LU are renowned for their wonderful poster art. It's shocking to see their standards drop.